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Corrections to OCR mistakes provided by Tom Murphy.

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NOTES_ON_OPTICAL_PRINTER_TECHNIQUE.md
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@ -99,7 +99,7 @@ At `M > 1` a part of the original frame is photographed at a size which fills th
**!["M = 3" Graphic depicting two frames with a lens closer to the right projection source image with the lamp demonstrating an enlargement](img/image_3.jpg)** **!["M = 3" Graphic depicting two frames with a lens closer to the right projection source image with the lamp demonstrating an enlargement](img/image_3.jpg)**
If, starting from the 1:1 setup, the lens is moved farther from the gate, then the camera must also be moved back, farther from the gate, to keep the one film focused on the other. If, starting from the 1:1 setup, the lens is moved farther from the gate, then the camera must also be moved back, farther from the gate, to keep the one film focused on the other.
Then the magnification is loser than 1. Then the magnification is less than 1.
At `M < 1` the whole of the original frame is photographed at a size which does not fill the whole of the print frame. At `M < 1` the whole of the original frame is photographed at a size which does not fill the whole of the print frame.
The remainder of the print frame is filled with a photograph of the gate as it surrounds the original frame (ideally perfectly black). The remainder of the print frame is filled with a photograph of the gate as it surrounds the original frame (ideally perfectly black).
@ -115,7 +115,7 @@ But for each position of the camera (except the 1:1 position) there are two corr
The printer gate may hold 8mm film and the printer camera 16mm, or vice versa. The printer gate may hold 8mm film and the printer camera 16mm, or vice versa.
With a `M = 2` setup an 8mm original frame is photographed onto a whole 16mm frame. With a `M = 2` setup an 8mm original frame is photographed onto a whole 16mm frame.
With an `M = 1/2` setup a whole 16mm original frame is photographed onto an 8mm frame. With an `M = 1/2` setup a whole 16mm original frame is photographed onto an 8mm frame.
Conversion between any two film gauges is possible this way, provided the frames have the sane proportions, as 8mm, super 8mm, 16mm, and some 35mm do. Conversion between any two film gauges is possible this way, provided the frames have the same proportions, as 8mm, super 8mm, 16mm, and some 35mm do.
<a name="blowup-sharpness"></a> <a name="blowup-sharpness"></a>
@ -142,10 +142,10 @@ Likewise for 16mm to 35mm.
A lens well-corrected for `M = 1` is less well-corrected for `M = 2` (or `M = 1/2`). A lens well-corrected for `M = 1` is less well-corrected for `M = 2` (or `M = 1/2`).
A lens well-corrected for `M = 2` is A lens well-corrected for `M = 2` is
less well-corrected for ` M = 4` (or `M = 1/2`). less well-corrected for ` M = 4` (or `M = 1/4`).
Etc. Etc.
(Floating elements improve this.) (Floating elements improve this.)
A lens well-corrected for `M = 1` for a larger format is lees than ideal for `M = 1` for a smaller format. A lens well-corrected for `M = 1` for a larger format is less than ideal for `M = 1` for a smaller format.
With such specialization (and expense) in optical printer optics what is the hope for the $50 50mm enlarger lens, optimized for `M = .1` and much too large a format? With such specialization (and expense) in optical printer optics what is the hope for the $50 50mm enlarger lens, optimized for `M = .1` and much too large a format?
Not bad, provided the sharpest aperture is found and heeded and focusing technique is good. Not bad, provided the sharpest aperture is found and heeded and focusing technique is good.
Also, for `M != 1` an asymmetrical lens should be mounted the right way, which is usually with its smaller glass facing the smaller image. Also, for `M != 1` an asymmetrical lens should be mounted the right way, which is usually with its smaller glass facing the smaller image.
@ -189,7 +189,7 @@ Printer focusing procedure is different at different magnification.
At 1:1 the camera, not the lens, is moved for focusing. At 1:1 the camera, not the lens, is moved for focusing.
Only at magnifications greater than about 1.4 is it better to move the lens for focusing. Only at magnifications greater than about 1.4 is it better to move the lens for focusing.
Near the 1:1 setup lens motion has no focusing effect. Near the 1:1 setup lens motion has no focusing effect.
With the camera fixed in its 1:1 position lens motion: adjusts magnification between about M=.96 and M=1.04 (at f/5.6). With the camera fixed in its 1:1 position lens motion adjusts magnification between about `M = .96` and `M = 1.04` (at f/5.6).
<a name="focusing-aperature"></a> <a name="focusing-aperature"></a>
@ -250,11 +250,11 @@ For example, if the lens is raised a bit...
**![Graphic depicting a lens' central position between two frames demonstrating a rise adjusting framing](img/image_5.jpg)** **![Graphic depicting a lens' central position between two frames demonstrating a rise adjusting framing](img/image_5.jpg)**
At 1:1 moving the lens up a distance d raises the viewed field by twice d. At 1:1 moving the lens up a distance `d` raises the viewed field by twice `d`.
Likewise for down, right, and left. Likewise for down, right, and left.
At `M > 1` lateral adjustment effects a scan of the original frame. At `M > 1` lateral adjustment effects a scan of the original frame.
This is not geometrically equivalent to a pan, bad it been made in the original photography. This is not geometrically equivalent to a pan, had it been made in the original photography.
On simple optical printers the only lateral adjustment is of the lens (rather than the heavier camera or gate). On simple optical printers the only lateral adjustment is of the lens (rather than the heavier camera or gate).
This is geometrically adequate. This is geometrically adequate.
@ -280,7 +280,7 @@ The photograph made while the coincidence is seen is the aimframe.
Every groundglass has some permanent details, even if only its flaws. Every groundglass has some permanent details, even if only its flaws.
The field edge is a poor choice of detail if the mask is thick or if the eyepiece is aberrated at the edge. The field edge is a poor choice of detail if the mask is thick or if the eyepiece is aberrated at the edge.
Two points of detail are enough for a well~aligned printer, three points for a suspect one. Two points of detail are enough for a well-aligned printer, three points for a suspect one.
A reticle made on high resolution film may be attached to the groundglass to add details. A reticle made on high resolution film may be attached to the groundglass to add details.
Small patterns of concentric circles and other patterns which self-moiré are ideal. Small patterns of concentric circles and other patterns which self-moiré are ideal.
@ -291,7 +291,7 @@ Focusing must be completed before the final adjustment to the aimframe.
It is convenient to incorporate a focusing target in the aimframe. It is convenient to incorporate a focusing target in the aimframe.
The aimframe has validity only for the camera in which it was made. The aimframe has validity only for the camera in which it was made.
It does not depend on the accuracy of the cameras reflex viewing system, only the stability of the system. It does not depend on the accuracy of the camera's reflex viewing system, only the stability of the system.
Whenever there is doubt about the validity of the aimframe, such as after a camera repair or because of wear to the film, Whenever there is doubt about the validity of the aimframe, such as after a camera repair or because of wear to the film,
The old aimframe can be registered in the printer gate, aimed The old aimframe can be registered in the printer gate, aimed
on, and photographed to make a newly valid aimframe. on, and photographed to make a newly valid aimframe.
@ -341,7 +341,7 @@ To make a frameline adjustment, if the reflex viewfinder is well-set, then even
If the reflex viewfinder is untrustworthy, then a camera gate focuser can be used. If the reflex viewfinder is untrustworthy, then a camera gate focuser can be used.
Or this method: register in the printer gate a bipack of the original with any file shot in the printer camera. Or this method: register in the printer gate a bipack of the original with any file shot in the printer camera.
Determine how much vertical adjustment separates their framelines. Determine how much vertical adjustment separates their framelines.
Make that puch adjustment to the aimframe setup. Make that much adjustment to the aimframe setup.
The framelines of the original can always be eliminated from the print by setting the magnification slightly greater than 1. The framelines of the original can always be eliminated from the print by setting the magnification slightly greater than 1.
@ -355,7 +355,7 @@ A priori, a film of an alphabet could be any of these eight ways.
Each sketch shows emulsion facing out. Each sketch shows emulsion facing out.
For double perf film there are only four ways. For double perf film there are only four ways.
The a and b ways become the same. The `a` and `b` ways become the same.
Camera original is (IIIa). Camera original is (IIIa).
@ -425,14 +425,15 @@ This can be avoided by randomizing the frames to be doubled while still choosing
For poorly designed condenser systems a diffuser will even the illumination over the frame. For poorly designed condenser systems a diffuser will even the illumination over the frame.
Other than for this, diffusers are located immediately behind the original film to alter image quality in several ways: Other than for this, diffusers are located immediately behind the original film to alter image quality in several ways:
1. reduce the appearance of scratches on the film base; 1. reduce the appearance of scratches on the film base;
2. soften the appearance of grain, and without reducing resolution *per se*, reduce sharpness; 2. soften the appearance of grain, and without reducing resolution *per se*, reduce sharpness;
3. reduce the apparent oontrast of B&W originals, approximating the tonality in contact printing. 3. reduce the apparent contrast of B&W originals, approximating the tonality in contact printing.
Opal glass, a more extreme diffuser than groundglass, is more effective in each of the three ways. Opal glass, a more extreme diffuser than groundglass, is more effective in each of the three ways.
An opal glase oan reduce exposure by 4 or even more stops. An opal glass can reduce exposure by 4 or even more stops.
An accidental or for;otten opal glass can devastate an exposure! An accidental or forgotten opal glass can devastate an exposure!
<a name="uv-filter"></a> <a name="uv-filter"></a>
@ -466,7 +467,7 @@ Printing B&W to B&W with a non-apochromatic lens, a green filter can improve sha
## FILTER LOCATION ## FILTER LOCATION
The spectral effect of a filter on the photography is the same wherever it is located between the lamp and the rawatock. The spectral effect of a filter on the photography is the same wherever it is located between the lamp and the rawstock.
The optical effect of a filter can't be good, so it ought to be located on the illumination side of the original rather than on the image-formation side. The optical effect of a filter can't be good, so it ought to be located on the illumination side of the original rather than on the image-formation side.
(There, flaws in filters are harmless. A color filter may even be perforated to reduce its effective saturation.) (There, flaws in filters are harmless. A color filter may even be perforated to reduce its effective saturation.)
@ -478,7 +479,7 @@ In optical printing as in original photography, the exposure is adjustable, and
But there is a difference. But there is a difference.
The natural scene may exhibit an immense brightness range, from the brightest light sources (and secondary sources--reflections) to the darkest light sinks. The natural scene may exhibit an immense brightness range, from the brightest light sources (and secondary sources--reflections) to the darkest light sinks.
The film original is limited in brightness range, between the clear of the base and the maximum density of the emulsion. The film original is limited in brightness range, between the clear of the base and the maximum density of the emulsion.
This could be an 11 atop range for some color reversal films, but only about 6 stops for a negative original. This could be an 11 stop range for some color reversal films, but only about 6 stops for a negative original.
The exposure problem in original photography is to decide what portion of the immense brightness range to capture on the film. The exposure problem in original photography is to decide what portion of the immense brightness range to capture on the film.
The exposure problem in optical printing is to decide how to capture on the print film the whole of the original image range. The exposure problem in optical printing is to decide how to capture on the print film the whole of the original image range.
@ -502,7 +503,7 @@ Using the variable shutter for exposure adjustment makes its use for fades or di
**LENS APERTURE** - This is a silly way to adjust exposure. **LENS APERTURE** - This is a silly way to adjust exposure.
Changing lens aperture changes picture sharpness. Changing lens aperture changes picture sharpness.
Except for fine expoeure adjustments (+/1 1/2 stop) the lens is best left at its sharpest opening. Except for fine exposure adjustments (± 1/2 stop) the lens is best left at its sharpest opening.
(For exposure testing and other dirty work, lens aperture is a handy exposure adjuster.) (For exposure testing and other dirty work, lens aperture is a handy exposure adjuster.)
@ -511,7 +512,7 @@ But it introduces color changes.
Also, modern halogen lamps lose life at prolonged low voltages. Also, modern halogen lamps lose life at prolonged low voltages.
Voltage adjustment is a practical means for fine exposure adjustment. Voltage adjustment is a practical means for fine exposure adjustment.
Dropping the voltage 10% reduces the light about t stop while changing the color about `CCO5Y+CCO2M`. Dropping the voltage 10% reduces the light about 1/2 stop while changing the color about `CCO5Y+CCO2M`.
**POLARIZERS** - Two polarizers, one rotatable, is a cute way to adjust exposure. **POLARIZERS** - Two polarizers, one rotatable, is a cute way to adjust exposure.
But sheet polarizers get hot and have short lives in the optical printer. But sheet polarizers get hot and have short lives in the optical printer.
@ -567,7 +568,7 @@ The values are informative for comparison of similar stocks.
For many printing films ASA and related values are undefinable. For many printing films ASA and related values are undefinable.
The optical printer will have exposure standards unto itself, determined by testing. The optical printer will have exposure standards unto itself, determined by testing.
Once it is known how to beat expose, a certain original onto a certain print film, good estimates can be made for similar originals or similar print films. Once it is known how to best expose a certain original onto a certain print film, good estimates can be made for similar originals or similar print films.
<a name="right-exposure"></a> <a name="right-exposure"></a>
@ -585,8 +586,8 @@ This avoids the print film's toe.
The best reversal optical print of this will match it. The best reversal optical print of this will match it.
And so on. And so on.
Starting from negative camera Original the best interpositive print has some density in the highlights. Starting from negative camera original the best interpositive print has some density in the highlights.
The beat internegative is a little darker than the original negative. The best internegative is a little darker than the original negative.
A further interpositive would best match the first one, etc. A further interpositive would best match the first one, etc.
<a name="generations"></a> <a name="generations"></a>
@ -605,7 +606,7 @@ PXR and 7361 are gamma 1 B&W reversal stocks.
For B&W negative there is the option of alternating gammas above and below 1--7366 with gamma 1.4 and 7234 with gamma For B&W negative there is the option of alternating gammas above and below 1--7366 with gamma 1.4 and 7234 with gamma
.7--and multiply out to 1. .7--and multiply out to 1.
There are no available reversal stocks with Gamma less than 1. There are no available reversal stocks with gamma less than 1.
For color reversal ECO, until its disappearance in 1985, was a favorite gamma 1 camera stock and ECO--ECO--ECO--etc. was the classical printing scheme. For color reversal ECO, until its disappearance in 1985, was a favorite gamma 1 camera stock and ECO--ECO--ECO--etc. was the classical printing scheme.
ECO--7399--7399--etc. was a similar, possibly better scheme. ECO--7399--7399--etc. was a similar, possibly better scheme.
@ -616,7 +617,7 @@ For this, the release print too will be on 7399.
Original Kodachrome follows the VNF scheme. Original Kodachrome follows the VNF scheme.
7399 stock misbehaves with exposure times longer than about 7399 stock misbehaves with exposure times longer than about
-1 second. .1 second.
For B&W reversal PXR--PXR--PXR--etc. is the classical printing scheme. For B&W reversal PXR--PXR--PXR--etc. is the classical printing scheme.
PXR--7361--7361--etc. is a similar, slightly better PXR--7361--7361--etc. is a similar, slightly better
@ -657,7 +658,7 @@ This is the paradox, or the folly, of optical printing.
## BELLOWS FORMULA ## BELLOWS FORMULA
Exposure way change with magnification. Exposure may change with magnification.
A "bellows formula" works for most printer lenses and most illumination systems. A "bellows formula" works for most printer lenses and most illumination systems.
It prescribes... It prescribes...
@ -729,10 +730,10 @@ Fine callibration should not be attempted for there is play in the mechanism.
## LINEAR FADE ## LINEAR FADE
The linear fadeout, compared with the log fadeout of the sane length, starts slower and finishes faster. The linear fadeout, compared with the log fadeout of the same length, starts slower and finishes faster.
With a variable shutter a linear fadeout from a positive original 16 made by subtracting each new frame a certain angles. With a variable shutter a linear fadeout from a positive original is made by subtracting each new frame a certain angles.
For simplicity, take a linear fadeout to be complete at O°. For simplicity, take a linear fadeout to be complete at 0°.
For example, with a 180° shutter a 30 frame linear fade changes 6° each frame. For example, with a 180° shutter a 30 frame linear fade changes 6° each frame.
ND filters can be used to make a linear fade. ND filters can be used to make a linear fade.
@ -749,7 +750,7 @@ The "look", and perhaps the "meaning", of a fade depends on how the exposure cha
## FADES IN ORIGINAL ## FADES IN ORIGINAL
A fade made from a scene looks distinctly different from one made from a film image of the scene if the scene containga bright highlights. A fade made from a scene looks distinctly different from one made from a film image of the scene if the scene contains bright highlights.
Made from the scene, the highlights shine on when the remainder of the scene is practically black. Made from the scene, the highlights shine on when the remainder of the scene is practically black.
Made from the film, the highlights follow the other light parts of the picture. Made from the film, the highlights follow the other light parts of the picture.
@ -769,14 +770,14 @@ CHART C
| .15 | 70.8% | 120° | ____ | | .15 | 70.8% | 120° | ____ |
| .20 | 63.1% | 107° | ____ | | .20 | 63.1% | 107° | ____ |
| .25 | 56.2% | 96° | ____ | | .25 | 56.2% | 96° | ____ |
| .30 | 50.1% | 95° | ____ | | .30 | 50.1% | 85° | ____ |
| .35 | 44.7% | 76° | ____ | | .35 | 44.7% | 76° | ____ |
| .40 | 39.8% | 68° | ____ | | .40 | 39.8% | 68° | ____ |
| .45 | 35.5% | 60° | ____ | | .45 | 35.5% | 60° | ____ |
| .50 | 31.6% | 54° | ____ | | .50 | 31.6% | 54° | ____ |
| .55 | 28.2% | 48° | ____ | | .55 | 28.2% | 48° | ____ |
| .60 | 25.1% | 43° | ____ | | .60 | 25.1% | 43° | ____ |
| .65 | 22.48 | 38° | ____ | | .65 | 22.4% | 38° | ____ |
| .70 | 20.0% | 34° | ____ | | .70 | 20.0% | 34° | ____ |
| .75 | 17.8% | 30° | ____ | | .75 | 17.8% | 30° | ____ |
| .80 | 15.8% | 27° | ____ | | .80 | 15.8% | 27° | ____ |
@ -791,10 +792,10 @@ CHART C
| 1.25 | 5.62% | 9.6° | ____ | | 1.25 | 5.62% | 9.6° | ____ |
| 1.30 | 5.01% | 8.5° | ____ | | 1.30 | 5.01% | 8.5° | ____ |
| 1.35 | 4.47% | 7.6° | ____ | | 1.35 | 4.47% | 7.6° | ____ |
| 1.40 | 3.98% | 6.8 | ____ | | 1.40 | 3.98% | 6.8° | ____ |
| 1.45 | 3.55% | 6.0° | ____ | | 1.45 | 3.55% | 6.0° | ____ |
| 1.50 | 3.16% | 5.4° | ____ | | 1.50 | 3.16% | 5.4° | ____ |
| 1.55 | 2.52% | 4.8° | ____ | | 1.55 | 2.82% | 4.8° | ____ |
| 1.60 | 2.51% | 4.3° | ____ | | 1.60 | 2.51% | 4.3° | ____ |
| 1.65 | 2.24% | 3.8° | ____ | | 1.65 | 2.24% | 3.8° | ____ |
| 1.70 | 2.00% | 3.4° | ____ | | 1.70 | 2.00% | 3.4° | ____ |
@ -831,13 +832,13 @@ CHART C
| +N.D. | % of Full Shutter | 180° | 130° | 235° | | +N.D. | % of Full Shutter | 180° | 130° | 235° |
|-------|-------------------|------|------|------| |-------|-------------------|------|------|------|
| .00 | 100 | 180 | 130 | 235 | | .00 | 100 | 180 | 130 | 235 |
| .05 | 89.1 | 140 | 115 | 209 | | .05 | 89.1 | 160 | 115 | 209 |
| .10 | 79.4 | 143 | 103 | 186 | | .10 | 79.4 | 143 | 103 | 186 |
| .15 | 70.8 | 127 | 92 | 166 | | .15 | 70.8 | 127 | 92 | 166 |
| .20 | 63.1 | 114 | 82 | 148 | | .20 | 63.1 | 114 | 82 | 148 |
| .25 | 56.2 | 101 | 73 | 132 | | .25 | 56.2 | 101 | 73 | 132 |
| .30 (1 stop)| 50.1| 90 | 65 | 117 | | .30 (1 stop)| 50.1| 90 | 65 | 117 |
| .35 | 44.7 | 80 | 53 | 105 | | .35 | 44.7 | 80 | 58 | 105 |
| .40 | 39.8 | 72 | 52 | 94 | | .40 | 39.8 | 72 | 52 | 94 |
| .45 | 35.5 | 64 | 46 | 83 | | .45 | 35.5 | 64 | 46 | 83 |
| .50 | 31.6 | 57 | 41 | 74 | | .50 | 31.6 | 57 | 41 | 74 |
@ -859,7 +860,7 @@ CHART C
| 1.30| 5.01 | 9 | 7 | 12 | | 1.30| 5.01 | 9 | 7 | 12 |
| 1.35| 4.47 | 8 | 6 | 11 | | 1.35| 4.47 | 8 | 6 | 11 |
| 1.40| 3.98 | 7.2 | 5 | 9 | | 1.40| 3.98 | 7.2 | 5 | 9 |
| 1,45| 3.55 | 6.4 | 5 | 8 | | 1.45| 3.55 | 6.4 | 5 | 8 |
| 1.50 (5 stops)| 3.16| 5.7 | 4 | 7 | | 1.50 (5 stops)| 3.16| 5.7 | 4 | 7 |
\newpage \newpage
@ -873,7 +874,7 @@ There are three basic types of image superposition, named according to how they
Pictures A & B combined by... Pictures A & B combined by...
1. <span class="underline">Double exposure from positives.</span> The print film is eared twice, once from A's positive, once from B's positive. 1. <span class="underline">Double exposure from positives.</span> The print film is exposed twice, once from A's positive, once from B's positive.
2. <span class="underline">Double exposure from negatives.</span> The print film is exposed twice, once from A's negative, once from B's negative. 2. <span class="underline">Double exposure from negatives.</span> The print film is exposed twice, once from A's negative, once from B's negative.
3. <span class="underline">Bipack.</span> Two films, either A's and B's positives, or else A's and B's negatives, are inserted together in the printer gate. The print film is exposed once, from this pair. 3. <span class="underline">Bipack.</span> Two films, either A's and B's positives, or else A's and B's negatives, are inserted together in the printer gate. The print film is exposed once, from this pair.
@ -888,7 +889,7 @@ With (2), darkness dominates.
The result is nearly the darker of the two tones. The result is nearly the darker of the two tones.
With (3), there is contrastification which complicates the tone combination. With (3), there is contrastification which complicates the tone combination.
If a bipack is examined ray (unprinted) wherever both images are clear the bipack is clear. If a bipack is examined raw (unprinted) wherever both images are clear the bipack is clear.
Wherever either image is black the bipack is at least that black. Wherever either image is black the bipack is at least that black.
Wherever both images are black the bipack is doubly black. Wherever both images are black the bipack is doubly black.
The bipack, which appears dark, has a tonal range doubling that of the The bipack, which appears dark, has a tonal range doubling that of the
@ -903,7 +904,7 @@ With 2 stops increase there is darkness domination.
## GAMMA & BIPACK ## GAMMA & BIPACK
If the bipack is printed onto gamma $ material, to reduce the contrast to normal, it is a true tonal blender, without dominance, of the two images. If the bipack is printed onto gamma 1/2 material, to reduce the contrast to normal, it is a true tonal blender, without dominance, of the two images.
As the graphs below show, the gamma 1/2 bipack is the mean between the type (1) and type (2) double exposures. As the graphs below show, the gamma 1/2 bipack is the mean between the type (1) and type (2) double exposures.
<a name="incidentally"></a> <a name="incidentally"></a>
@ -916,7 +917,7 @@ Four idealized graphs summarize the three basic types of superposition and the g
Example: Example:
> 4 has density .75 and B has density 1.75 in one place. From the first graph, the double exposure from positives has density about 1.0 in that place. > `A` has density .75 and `B` has density 1.75 in one place. From the first graph, the double exposure from positives has density about 1.0 in that place.
**![Graphics depicting DOUBLE EXPOSURE FROM POS'S, BIPACK (1.0 COMPENS) DOUBLE EXPOSURE FROM NEGS and GAMMA 1/2 BIPACK](img/image_8.jpg)** **![Graphics depicting DOUBLE EXPOSURE FROM POS'S, BIPACK (1.0 COMPENS) DOUBLE EXPOSURE FROM NEGS and GAMMA 1/2 BIPACK](img/image_8.jpg)**
@ -928,7 +929,7 @@ For a bipack it doesn't matter which film is in front.
Also the two may be optically instead of mechanically bipacked. Also the two may be optically instead of mechanically bipacked.
In some multi-head optical printers the films are in separate gates, ones projection becoming the other's illumination. In some multi-head optical printers the films are in separate gates, ones projection becoming the other's illumination.
In a simple printer one film may be in the gate and the other in the camera, in front of the print film. In a simple printer one film may be in the gate and the other in the camera, in front of the print film.
Any way, the two films ehare one exposure adjustment and filtration. Any way, the two films share one exposure adjustment and filtration.
When films will be physically bipacked they should first be wiped with a lubricating film cleaner. When films will be physically bipacked they should first be wiped with a lubricating film cleaner.
This is good practice for all optical printing when delicate originals receive heavy handling. This is good practice for all optical printing when delicate originals receive heavy handling.
@ -941,7 +942,7 @@ For superpositions from random pictorial originals:
For double exposures, the typical exposure adjustment is one stop of decrease from normal, during each exposure. For double exposures, the typical exposure adjustment is one stop of decrease from normal, during each exposure.
> With this adjustment a double exposure of picture A with picture A ie the same as a single normal exposure of A. > With this adjustment a double exposure of picture A with picture A is the same as a single normal exposure of A.
For bipacks there is no recipe. For bipacks there is no recipe.
Exposure adjustment is extremely dependent on which tones coincide with Exposure adjustment is extremely dependent on which tones coincide with
@ -949,7 +950,7 @@ which.
The adjustment is an increase from normal. The adjustment is an increase from normal.
In ignorance of the originals (why?) and ignorance of the intentions (why?) guess 2 1/2 stops increase. In ignorance of the originals (why?) and ignorance of the intentions (why?) guess 2 1/2 stops increase.
> No exposure adjustment can make a bipack of picture A with picture A the same as picture. A printed the same. But a gamma 1/2 bipack of picture A with picture A is the same as picture. > No exposure adjustment can make a bipack of picture A with picture A the same as picture A printed the same. But a gamma 1/2 bipack of picture A with picture A is the same as picture A.
<a name="special-originals"></a> <a name="special-originals"></a>
@ -958,9 +959,10 @@ In ignorance of the originals (why?) and ignorance of the intentions (why?) gues
For superpositions not from random pictorial originals tones might not combine at all. For superpositions not from random pictorial originals tones might not combine at all.
One image might fall on the other's black, or clear, and exposure compensation is different, perhaps unnecessary. One image might fall on the other's black, or clear, and exposure compensation is different, perhaps unnecessary.
With special, rigged, originale superposition is not image combination in the earlier sense but image apportionment--implantings and supplantings. With special, rigged, originals superposition is not image combination in the earlier sense but image apportionment--implantings and supplantings.
The rules of tone combination still apply, but trivially, and a simpler logic prevails. The rules of tone combination still apply, but trivially, and a simpler logic prevails.
Double exposing from positives, where one image is black the other image appears, unaffected by the double exposure. Double exposing from positives, where one image is black the other image appears, unaffected by the double exposure.
Where one image is very light it appears, hardly affected by the double exposure. Where one image is very light it appears, hardly affected by the double exposure.
@ -1041,42 +1043,51 @@ There are the same three basic types.
Double exposure from positives gives additive color mixture. Double exposure from positives gives additive color mixture.
Bipacking gives so-called subtractive color mixture. Bipacking gives so-called subtractive color mixture.
When bipacking color negatives the extra orange mask should be neutralized by filtering.) (When bipacking color negatives the extra orange mask should be neutralized by filtering.)
Double exposure from negatives gives something else. Double exposure from negatives gives something else.
For greys in the two images, combination is as for B&W. For greys in the two images, combination is as for B&W.
But for colors, not only are new colors produced but apparent brightnesses do not combine quite the same ae for B&W. But for colors, not only are new colors produced but apparent brightnesses do not combine quite the same as for B&W.
The dyes in Wratten CC filters Y, M, C are similar to those in color films. The dyes in Wratten CC filters Y, M, C are similar to those in color films.
Film colors can be simulated by packs of these filters and much can be learned about film color manipulation from familiarity with the filters and their combinations. Film colors can be simulated by packs of these filters and much can be learned about film color manipulation from familiarity with the filters and their combinations.
Example 1: Example 1:
> Image & is orange (`CC200Y`+`CC100M`) > Image A is orange (`CC200Y`+`CC100M`)
> Image B ts blue (`CC100M`+`CC200C`) >
> Image B is blue (`CC100M`+`CC200C`)
> Double exposure from positives gives a raspberry color (`CC7OM`+`ND.30`) > Double exposure from positives gives a raspberry color (`CC7OM`+`ND.30`)
>
> Double exposure from negatives gives a fairly dark greyish green (`CC7OY`+`CC70C`+`ND1.00`) > Double exposure from negatives gives a fairly dark greyish green (`CC7OY`+`CC70C`+`ND1.00`)
> Bipack, with 3 stop exposure compensation, gives a middle grey (`ND1.10`) > Bipack, with 3 stop exposure compensation, gives a middle grey (`ND1.10`)
Example 2: Example 2:
> Image A is maximum red (`CC250Y`+`CC250M`) > Image A is maximum red (`CC250Y`+`CC250M`)
>
> Image B is maximum green (`CC250Y`+`CC250C`) > Image B is maximum green (`CC250Y`+`CC250C`)
> Double exposure from positives gives yellow (`CC220Y`+`ND.3`) > Double exposure from positives gives yellow (`CC220Y`+`ND.3`)
> Double exposure from negatives givee black (`CC30Y`+`ND2.20`) >
> Double exposure from negatives gives black (`CC30Y`+`ND2.20`)
>
> Bipack, with 3 stop exposure compensation, gives brown (`CC9OY`+`ND1.60`) > Bipack, with 3 stop exposure compensation, gives brown (`CC9OY`+`ND1.60`)
Example 3: Example 3:
> Image A is a flesh (`CC30Y`+`CC20M`+`CC10C`) > Image A is a flesh (`CC30Y`+`CC20M`+`CC10C`)
>
> Image B is sky (`CC6OM`+`CC80C`) > Image B is sky (`CC6OM`+`CC80C`)
> Double exposure from positives gives (`CC12Y`+`CC36M`+`CC32C`) > Double exposure from positives gives (`CC12Y`+`CC36M`+`CC32C`)
>
> Double exposure from negatives gives (`CC18Y`+`CC45M`+`CC58C`) > Double exposure from negatives gives (`CC18Y`+`CC45M`+`CC58C`)
> Bipack, with 1 stop exposure compensation, gives (`CCSOM`+`CC60C`) >
> Bipack, with 1 stop exposure compensation, gives (`CC50M`+`CC60C`)
<a name="weighted-double-exposures"></a> <a name="weighted-double-exposures"></a>
@ -1099,14 +1110,14 @@ The traditional dissolve is a simultaneous (double exposed)linear fadeout of the
A simultaneous log fadeout and log fadein makes quite a lumpy dissolve (becoming dark midway, from positive images). A simultaneous log fadeout and log fadein makes quite a lumpy dissolve (becoming dark midway, from positive images).
Regular dissolves are planned as if for variable shutters. Regular dissolves are planned as if for variable shutters.
At each frame the shutter angles for the two exposures must sun to the full shutter angle. At each frame the shutter angles for the two exposures must sum to the full shutter angle.
ND equivalents can be found in Chart C and ND filters can be used to make the dissolve. ND equivalents can be found in Chart C and ND filters can be used to make the dissolve.
It is not necessary for the fadeout and the fadein to be the same or even of the same type. It is not necessary for the fadeout and the fadein to be the same or even of the same type.
Any chosen fadeout has a complementary fadein (found by subtractions from full shutter angle), and vice versa. Any chosen fadeout has a complementary fadein (found by subtractions from full shutter angle), and vice versa.
A dissolve from negative originals is made by pretending they are positives and following the method for positives. A dissolve from negative originals is made by pretending they are positives and following the method for positives.
No dissolve made from negative originale will look the same as a dissolve made from the corresponding positive originals. No dissolve made from negative originals will look the same as a dissolve made from the corresponding positive originals.
<a name="effects-dissolves"></a> <a name="effects-dissolves"></a>
@ -1137,12 +1148,12 @@ The clear film is faded in approximately logarithmically, and the negative is fa
## COLOR EXPOSURE ## COLOR EXPOSURE
The earlier discussione of exposure apply as well to color printing except that now color and brightness are adjustable. The earlier discussions of exposure apply as well to color printing except that now color and brightness are adjustable.
The adjustments are made primarily with CC filters and ND filters. The adjustments are made primarily with CC filters and ND filters.
A `CCY--` filter works roughly like an `ND.--` filter on just the blue part of the spectrum, while not affecting A `CCY--` filter works roughly like an `ND.--` filter on just the blue part of the spectrum, while not affecting
the rest of the spectrum. the rest of the spectrum.
Similarly a `CCM` filter cuts the green and a `CCC` filter cute the red. Similarly a `CCM` filter cuts the green and a `CCC` filter cuts the red.
ND filters could be eliminated by CC filters. ND filters could be eliminated by CC filters.
For example, `ND.30` is roughly `CC30Y`+`CC30M`+`CC30C`. For example, `ND.30` is roughly `CC30Y`+`CC30M`+`CC30C`.
This elimination is seldom practical and slightly inferior spectrally. This elimination is seldom practical and slightly inferior spectrally.
@ -1168,12 +1179,14 @@ The decision of "right exposure” is not easy.
It is tempting to shorten the test by varying CC and ND separately. It is tempting to shorten the test by varying CC and ND separately.
An ND value is fixed and the CC's varied. An ND value is fixed and the CC's varied.
A CC value is fixed and the ND's varied. A CC value is fixed and the ND's varied.
This makes decisions the more difficult, reguiring beat-color judgements on off-brightnees pictures and best-brightness judgements on off-color pictures. This makes decisions the more difficult, requiring best-color judgements on off-brightnees pictures and best-brightness judgements on off-color pictures.
This leads to simplietic criteria for decision. This leads to simplistic criteria for decision.
Example of a joint color and brightness test: Example of a joint color and brightness test:
> Each line in the chart represents CC filtration to be added to an initial guess of the right CC's. At each line make a series of ND variations surrounding an initial guess of the right ND. Perhaps the guess -.50, -.40, -.30, -.20, -.10, the guese itself, +.10, +.20, and +.30. The series is lopsided because the CC filtrations are all added to the CC guess. The 37 CC variations X the 9 ND variations = a 333 frame > Each line in the chart represents CC filtration to be added to an initial guess of the right CC's. At each line make a series of ND variations surrounding an initial guess of the right ND. Perhaps the guess -.50, -.40, -.30, -.20, -.10, the guess itself, +.10, +.20, and +.30. The series is lopsided because the CC filtrations are all added to the CC guess.
The 37 CC variations X the 9 ND variations = a 333 frame
test. test.
::: {.ymcTable} ::: {.ymcTable}
@ -1222,16 +1235,16 @@ test.
**![Diagram depicting the CC chart plotted on 3 axes: +M, +Y, +C](img/image_9.jpg)** **![Diagram depicting the CC chart plotted on 3 axes: +M, +Y, +C](img/image_9.jpg)**
A joint color and brightness test is a net spread over the logical region around an initial guesea, to catch the right exposure. A joint color and brightness test is a net spread over the logical region around an initial guess, to catch the right exposure.
The 37 line test in the example ia a rather fine 10-20-30 net usable when there is fair confidence in the initial guess. The 37 line test in the example ia a rather fine 10-20-30 net usable when there is fair confidence in the initial guess.
When there is better confidence in the guegse the test could be abridged to a 19 line 10-20 net (by omitting the lines with 30's) and the ND variations also reduced. When there is better confidence in the guess the test could be abridged to a 19 line 10-20 net (by omitting the lines with 30's) and the ND variations also reduced.
Very fine adjustments to color exposure, requiring tests with increments finer than `CC10` and `ND.10`, are only justified when two color exposures must match in two parts of one frame, or in rapidly succeeding frames. Very fine adjustments to color exposure, requiring tests with increments finer than `CC10` and `ND.10`, are only justified when two color exposures must match in two parts of one frame, or in rapidly succeeding frames.
As absolute adjustments, `CCO5` and `CCO25` are too likely to be defeated by the processing lab. As absolute adjustments, `CCO5` and `CCO25` are too likely to be defeated by the processing lab.
When there is little confidence in the guess the 10-20-30 net could be modified te a sparser 20-40-60 net (by doubling all values, including the ND variations). When there is little confidence in the guess the 10-20-30 net could be modified to a coarser 20-40-60 net (by doubling all values, including the ND variations).
This is still a 37 line test. This is still a 37 line test.
A 10-20-30-40-50-60 net would require a painfully long chart (253 lines!). A 10-20-30-40-50-60 net would require a painfully long chart (253 lines!).
A time and money and time problem arises: whether to do the huge test and determine the right exposure now, or to do a coarse test and almost determine the right exposure and perhaps have to do a finer retest. A time and money and time problem arises: whether to do the huge test and determine the right exposure now, or to do a coarse test and almost determine the right exposure and perhaps have to do a finer retest.
@ -1247,15 +1260,19 @@ Any combination of `CCY`, `CGM`, `CCC`, and also `CCB`, `CCG`, `CCR` can be redu
Method: Method:
> 1. change `CCB` to `COM`+`CCC` > 1. change `CCB` to `CCM`+`CCC`
>
> change `CCG` to `CCY`+`CCC` > change `CCG` to `CCY`+`CCC`
>
> change `CCR` to `CCY`+`CCM` > change `CCR` to `CCY`+`CCM`
> 2. add together all `CCY` > 2. add together all `CCY`
>
> add together all `CCM` > add together all `CCM`
>
> add together all `CCC` > add together all `CCC`
> 3. whichever of the three kinds has the smallest total in step 2 is eliminated. An equal amount of ND is added. An equal amount is subtracted from the regaining two kinds in step 2. > 3. whichever of the three kinds has the smallest total in step 2 is eliminated. An equal amount of ND is added. An equal amount is subtracted from the remaining two kinds in step 2.
4. count the number of CC filters in the initial and final packs. If the number has increased subtract `ND.O4` times the increase. If the number has decreased add `ND.O4` times the 4. count the number of CC filters in the initial and final packs. If the number has increased subtract `ND.O4` times the increase. If the number has decreased add `ND.O4` times the
decrease, decrease,
@ -1264,8 +1281,8 @@ Example: Reduce the pack `CC20Y`+`CC1OC`+`CC40R`
1. pack becomes `CC20Y`+`CC1OC`+`CC40Y`+`CC40M` 1. pack becomes `CC20Y`+`CC1OC`+`CC40Y`+`CC40M`
2. pack becomes `CC60Y`+`CC40M`+`CC10C` 2. pack becomes `CC60Y`+`CC40M`+`CC10C`
3. pack becomes `CC5OY`+`CC3OM`+`ND.10` 3. pack becomes `CC50Y`+`CC30M`+`ND.10`
4. pack becomes `CC5OY`+`CC3OM`+`ND.14` 4. pack becomes `CC50Y`+`CC30M`+`ND.14`
<a name="high-contrast-prints"></a> <a name="high-contrast-prints"></a>
@ -1310,7 +1327,7 @@ The original and print-wedge are kept for reference.
A hicon print of a hicon print is an exaggeration of an exaggeration of tone differences. A hicon print of a hicon print is an exaggeration of an exaggeration of tone differences.
All but. a three stop range of tones in the first hicon print clear or black in the second hicon. All but a three stop range of tones in the first hicon print clear or black in the second hicon.
But this three stop range resulted from a 3/4 stop range in the original. But this three stop range resulted from a 3/4 stop range in the original.
That is, all but a tiny part of the picture should now be either clear or black. That is, all but a tiny part of the picture should now be either clear or black.
@ -1329,7 +1346,7 @@ So this tone pattern is made starker and coarser by each contrast building step,
To avoid speckle, exposure must be adjusted at an early step, before there is black and clear in the pattern, to force the whole area to clear or to black. To avoid speckle, exposure must be adjusted at an early step, before there is black and clear in the pattern, to force the whole area to clear or to black.
To promote speckle, exposure is adjuated to hold the area in the greys through several steps. To promote speckle, exposure is adjusted to hold the area in the greys through several steps.
<a name="tone-isolation"></a> <a name="tone-isolation"></a>
@ -1339,13 +1356,13 @@ The parts of an original which share a single tone can be isolated by a hicon ma
1. make a negative hicon from the original with exposure adjusted to make the chosen tone go light, while tones somewhat lighter than it go dark; 1. make a negative hicon from the original with exposure adjusted to make the chosen tone go light, while tones somewhat lighter than it go dark;
2. bipack the original with the result of 1, printing onto hicon negative; 2. bipack the original with the result of 1, printing onto hicon negative;
3. additional contrast building steps ae necessary. 3. additional contrast building steps as necessary.
<a name="logic-of-mask-combination"></a> <a name="logic-of-mask-combination"></a>
## LOGIC OF MASK COMBINATION ## LOGIC OF MASK COMBINATION
Hicon masks being ail clear and black obey simplified rules of superposition. Hicon masks being all clear and black obey simplified rules of superposition.
With appropriate exposure, printing onto hicon negative, the rules are: With appropriate exposure, printing onto hicon negative, the rules are:
1. In double exposure, where there is black in both originals becomes clear. The rest becomes black. 1. In double exposure, where there is black in both originals becomes clear. The rest becomes black.
@ -1375,7 +1392,7 @@ It hints that lurking under every sharp exposure, many stops down, is a secondar
Bloom makee it impossible to separate darker tones of a continuous tone original with a hicon print by brute force of exposure adjustment. Bloom makee it impossible to separate darker tones of a continuous tone original with a hicon print by brute force of exposure adjustment.
Image spread is the result of edge unsharpness of both lena and film. Image spread is the result of edge unsharpness of both lens and film.
It makes the high contrast photography of tiny details, like fine print, difficult. It makes the high contrast photography of tiny details, like fine print, difficult.
Reversal processed hicon can show image shrink as well as image spread, and at exactly the right exposure, neither. Reversal processed hicon can show image shrink as well as image spread, and at exactly the right exposure, neither.
@ -1410,14 +1427,14 @@ One length is proceseed negative and the other is processed reversal.
They are the mask and countermask. They are the mask and countermask.
The original may be discarded. The original may be discarded.
For perfection, exposures are adjusted so the slight spreading of black in the negative print as equal to the slight spreading of clear in the reversal print. For perfection, exposures are adjusted so the slight spreading of black in the negative print is equal to the slight spreading of clear in the reversal print.
This mask and countermask might fit each other exactly, but if the setup wasn't exact 1:1 they will not fit their common source exactly, which may or may not matter. This mask and countermask might fit each other exactly, but if the setup wasn't exact 1:1 they will not fit their common source exactly, which may or may not matter.
Also the perfection of fit is with respect to the camera's registration system. Also the perfection of fit is with respect to the camera's registration system.
If the printer gate has a different system, then that perfection will soon be lost. If the printer gate has a different system, then that perfection will soon be lost.
This problem arose above in AIMFRAME. This problem arose above in AIMFRAME.
Simply, an optical printer with unmatched camera and gate registration mechanism, however excellent they may be, is doomed to registration defects in most affects. Simply, an optical printer with unmatched camera and gate registration mechanism, however excellent they may be, is doomed to registration defects in most effects.
<a name="feathered-masks"></a> <a name="feathered-masks"></a>
@ -1447,7 +1464,7 @@ Another picture is bipacked with the countermask and this is exposed onto the sa
The mask and countermask partition the frame for the two pictures. The mask and countermask partition the frame for the two pictures.
There is no black region and no region of pictorial double exposure in the print. There is no black region and no region of pictorial double exposure in the print.
Any pair of maak and countermask, where one proceeds gradually from all clear to all black (the other from all black to all clear) defines a wipe. Any pair of mask and countermask, where one proceeds gradually from all clear to all black (the other from all black to all clear) defines a wipe.
"Proceeds gradually” is subject to interpretation. "Proceeds gradually” is subject to interpretation.
Pretty nearly all image marriages fall into three categories: Pretty nearly all image marriages fall into three categories:
@ -1455,14 +1472,16 @@ Pretty nearly all image marriages fall into three categories:
**![Graphic depicting three examples of travelling matte marriages, I, II, and III](img/image_10.jpg)** **![Graphic depicting three examples of travelling matte marriages, I, II, and III](img/image_10.jpg)**
I. One region takes its shape from the things pictured within it. I. One region takes its shape from the things pictured within it.
II. One region takes its shape from the things pictured around it II. One region takes its shape from the things pictured around it
III. One region takes its shape from some not-pictured thing. III. One region takes its shape from some not-pictured thing.
<a name="mask-blackness"></a> <a name="mask-blackness"></a>
## MASK BLACKNESS ## MASK BLACKNESS
For successful image marriage the black of the hicon mask should be about 3 stops darker than the black of the picture which will f1l1 the black region. For successful image marriage the black of the hicon mask should be about 3 stops darker than the black of the picture which will fill the black region.
<a name="hicons-from-color-originals"></a> <a name="hicons-from-color-originals"></a>
@ -1471,7 +1490,7 @@ For successful image marriage the black of the hicon mask should be about 3 stop
7362 film is sensitive to blue light only. 7362 film is sensitive to blue light only.
For example, it cannot "see" the brightness difference between white and bright blue, or between yellow and red. For example, it cannot "see" the brightness difference between white and bright blue, or between yellow and red.
Color filtering with 7362 hae either no effect, or the effect of ND filtration. Color filtering with 7362 has either no effect, or the effect of ND filtration.
If a hicon mask is wanted, based on color differences, either If a hicon mask is wanted, based on color differences, either
@ -1481,12 +1500,13 @@ Then print this onto 7362.
or II. Print the original onto panchromatic hicon film (7369) with color filters as needed to separate the colors. or II. Print the original onto panchromatic hicon film (7369) with color filters as needed to separate the colors.
If two colors are different, there ia a filter which will make them record differently on panchromatic film. If two colors are different, there is a filter which will make them record differently on panchromatic film.
This is simpler when the two colors are on film than when they are in the natural world, because film colors are spectrally simpler. This is simpler when the two colors are on film than when they are in the natural world, because film colors are spectrally simpler.
To decide what filter best separates two film colors think of each color as made cf `CCY`, `CCM`, and `CCC`. To decide what filter best separates two film colors think of each color as made of `CCY`, `CCM`, and `CCC`.
Wherever the difference between the two colors is greatest (in the Y, the M, or the C) choose the complementary filter (B, G, R, respectively) in a strong (non-CC) version. Wherever the difference between the two colors is greatest (in the Y, the M, or the C) choose the complementary filter (B, G, R, respectively) in a strong (non-CC) version.
Example: Color 1 is a flesh (`CC30Y`+`CC2OM`+`CC10C`) Example: Color 1 is a flesh (`CC30Y`+`CC20M`+`CC10C`)
Color 2 is sky (`CC0Y`+`CC60M`+`CC80C`) Color 2 is sky (`CC0Y`+`CC60M`+`CC80C`)
@ -1501,7 +1521,7 @@ The greatest difference is in the cyan (C), so a red filter such as Wratten #29
1. Develop 6 minutes in D-11 @70° with continuous agitation. 1. Develop 6 minutes in D-11 @70° with continuous agitation.
2. Rinse 30 seconds in stopbath or water. 2. Rinse 30 seconds in stopbath or water.
3. Fix 1 1/2 minutes. 3. Fix 1 1/2 minutes.
4. (7369 only. Rinse 1 minute in as Clearing Agent.) 4. (7369 only. Rinse 1 minute in Hypo Clearing Agent.)
5. Wash 2 minutes in running water (longer for permanence). 5. Wash 2 minutes in running water (longer for permanence).
6. Dry. 6. Dry.
@ -1513,7 +1533,7 @@ The greatest difference is in the cyan (C), so a red filter such as Wratten #29
4. Clear 1 minute in CB-1 (solution of 90g Sodium Sulfite per liter of water). 4. Clear 1 minute in CB-1 (solution of 90g Sodium Sulfite per liter of water).
5. Rinse 2 minutes in water. During this time flash to light: 10 seconds at 1 foot from 100 watt lamp, or equivalent exposure. This is extremely approximate. The roomlight may be left on now. 5. Rinse 2 minutes in water. During this time flash to light: 10 seconds at 1 foot from 100 watt lamp, or equivalent exposure. This is extremely approximate. The roomlight may be left on now.
6. Develop 3 minutes in D-11. 6. Develop 3 minutes in D-11.
7. Rinse 30 seconds in etopbath or water. 7. Rinse 30 seconds in stopbath or water.
8. Fix 1 1/2 minutes. 8. Fix 1 1/2 minutes.
9. Wash 2 minutes in running water (longer for permanence). 9. Wash 2 minutes in running water (longer for permanence).
10. Dry. 10. Dry.

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@ -20,7 +22,6 @@
<p class="author">Dennis Couzin</p> <p class="author">Dennis Couzin</p>
<p class="date">March 1983</p> <p class="date">March 1983</p>
</header> </header>
<div class="indexTable"> <div class="indexTable">
<table> <table>
<tbody> <tbody>
@ -264,8 +265,6 @@
<div class="indexTableEnd"> <div class="indexTableEnd">
</div> </div>
<p>An optical printer is a device for photographing the frames of one film so as to make another film.</p> <p>An optical printer is a device for photographing the frames of one film so as to make another film.</p>
<p><strong><img src="../img/image_1.svg" alt="Graphic depicting labelled components camera, bellows, lens, gate and lamp" /></strong></p> <p><strong><img src="../img/image_1.svg" alt="Graphic depicting labelled components camera, bellows, lens, gate and lamp" /></strong></p>
<p>It consists essentially of a camera (C) connected by a bellows (B) to a lens (L) aimed at a film in a gate (G) illuminated from behind by a lamp (I).</p> <p>It consists essentially of a camera (C) connected by a bellows (B) to a lens (L) aimed at a film in a gate (G) illuminated from behind by a lamp (I).</p>
@ -278,12 +277,12 @@
<p><strong><img src="../img/image_2.svg" alt="“M = 1” Graphic depicting two frames with a lens at their midpoint with a lightbulb illuminating from the right" /></strong></p> <p><strong><img src="../img/image_2.svg" alt="“M = 1” Graphic depicting two frames with a lens at their midpoint with a lightbulb illuminating from the right" /></strong></p>
<p>If the lens is moved closer to the gate, then the camera must be moved back, farther from the gate, to keep the one film focused on the other. Then the magnification is greater than 1. At <code>M &gt; 1</code> a part of the original frame is photographed at a size which fills the whole of the print frame.</p> <p>If the lens is moved closer to the gate, then the camera must be moved back, farther from the gate, to keep the one film focused on the other. Then the magnification is greater than 1. At <code>M &gt; 1</code> a part of the original frame is photographed at a size which fills the whole of the print frame.</p>
<p><strong><img src="../img/image_3.svg" alt="“M = 3” Graphic depicting two frames with a lens closer to the right projection source image with the lamp demonstrating an enlargement" /></strong></p> <p><strong><img src="../img/image_3.svg" alt="“M = 3” Graphic depicting two frames with a lens closer to the right projection source image with the lamp demonstrating an enlargement" /></strong></p>
<p>If, starting from the 1:1 setup, the lens is moved farther from the gate, then the camera must also be moved back, farther from the gate, to keep the one film focused on the other. Then the magnification is loser than 1. At <code>M &lt; 1</code> the whole of the original frame is photographed at a size which does not fill the whole of the print frame. The remainder of the print frame is filled with a photograph of the gate as it surrounds the original frame (ideally perfectly black).</p> <p>If, starting from the 1:1 setup, the lens is moved farther from the gate, then the camera must also be moved back, farther from the gate, to keep the one film focused on the other. Then the magnification is less than 1. At <code>M &lt; 1</code> the whole of the original frame is photographed at a size which does not fill the whole of the print frame. The remainder of the print frame is filled with a photograph of the gate as it surrounds the original frame (ideally perfectly black).</p>
<p><strong><img src="../img/image_4.svg" alt="“M = 1/3” Graphic depicting two frames with a lens closer to the left camera image demonstrating a reduction" /></strong></p> <p><strong><img src="../img/image_4.svg" alt="“M = 1/3” Graphic depicting two frames with a lens closer to the left camera image demonstrating a reduction" /></strong></p>
<p>For each position of the lens there is exactly one correct (focused) position for the camera. But for each position of the camera (except the 1:1 position) there are two correct positions for the lens. One gives <code>M &gt; 1</code>, the other <code>M &lt; 1</code>.</p> <p>For each position of the lens there is exactly one correct (focused) position for the camera. But for each position of the camera (except the 1:1 position) there are two correct positions for the lens. One gives <code>M &gt; 1</code>, the other <code>M &lt; 1</code>.</p>
<p><a name="blowup-and-reduction"></a></p> <p><a name="blowup-and-reduction"></a></p>
<h2 id="blowup-reduction">BLOWUP &amp; REDUCTION</h2> <h2 id="blowup-reduction">BLOWUP &amp; REDUCTION</h2>
<p>The printer gate may hold 8mm film and the printer camera 16mm, or vice versa. With a <code>M = 2</code> setup an 8mm original frame is photographed onto a whole 16mm frame. With an <code>M = 1/2</code> setup a whole 16mm original frame is photographed onto an 8mm frame. Conversion between any two film gauges is possible this way, provided the frames have the sane proportions, as 8mm, super 8mm, 16mm, and some 35mm do.</p> <p>The printer gate may hold 8mm film and the printer camera 16mm, or vice versa. With a <code>M = 2</code> setup an 8mm original frame is photographed onto a whole 16mm frame. With an <code>M = 1/2</code> setup a whole 16mm original frame is photographed onto an 8mm frame. Conversion between any two film gauges is possible this way, provided the frames have the same proportions, as 8mm, super 8mm, 16mm, and some 35mm do.</p>
<p><a name="blowup-sharpness"></a></p> <p><a name="blowup-sharpness"></a></p>
<h2 id="blowup-sharpness">BLOWUP SHARPNESS</h2> <h2 id="blowup-sharpness">BLOWUP SHARPNESS</h2>
<p>A 16mm picture of a flea can be just as sharp as a 16mm picture of an elephant. But a 16mm picture of an 8mm picture cannot be expected to be as sharp as a 16mm picture of a 16mm picture. Pictures differ from things in having very limited detail. The 16mm blowup, even if it preserves all the pictorial detail of the 8mm original, spreads it out, so the blowup is less sharp absolutely than the original.</p> <p>A 16mm picture of a flea can be just as sharp as a 16mm picture of an elephant. But a 16mm picture of an 8mm picture cannot be expected to be as sharp as a 16mm picture of a 16mm picture. Pictures differ from things in having very limited detail. The 16mm blowup, even if it preserves all the pictorial detail of the 8mm original, spreads it out, so the blowup is less sharp absolutely than the original.</p>
@ -291,7 +290,7 @@
<p>An 8mm original blown up to 16mm and projected will appear sharper than the same 8mm original optically printed onto 8mm and projected. If the blowup optics are good this is even true when the 1:1 printing is by contact. Likewise for 16mm to 35mm. (This is all due to the print film being in effect twice as sharp and half as grainy in a bigger frame.)</p> <p>An 8mm original blown up to 16mm and projected will appear sharper than the same 8mm original optically printed onto 8mm and projected. If the blowup optics are good this is even true when the 1:1 printing is by contact. Likewise for 16mm to 35mm. (This is all due to the print film being in effect twice as sharp and half as grainy in a bigger frame.)</p>
<p><a name="printer-lenses"></a></p> <p><a name="printer-lenses"></a></p>
<h2 id="printer-lenses">PRINTER LENSES</h2> <h2 id="printer-lenses">PRINTER LENSES</h2>
<p>A lens well-corrected for <code>M = 1</code> is less well-corrected for <code>M = 2</code> (or <code>M = 1/2</code>). A lens well-corrected for <code>M = 2</code> is less well-corrected for <code>M = 4</code> (or <code>M = 1/2</code>). Etc. (Floating elements improve this.) A lens well-corrected for <code>M = 1</code> for a larger format is lees than ideal for <code>M = 1</code> for a smaller format. With such specialization (and expense) in optical printer optics what is the hope for the $50 50mm enlarger lens, optimized for <code>M = .1</code> and much too large a format? Not bad, provided the sharpest aperture is found and heeded and focusing technique is good. Also, for <code>M != 1</code> an asymmetrical lens should be mounted the right way, which is usually with its smaller glass facing the smaller image.</p> <p>A lens well-corrected for <code>M = 1</code> is less well-corrected for <code>M = 2</code> (or <code>M = 1/2</code>). A lens well-corrected for <code>M = 2</code> is less well-corrected for <code>M = 4</code> (or <code>M = 1/4</code>). Etc. (Floating elements improve this.) A lens well-corrected for <code>M = 1</code> for a larger format is less than ideal for <code>M = 1</code> for a smaller format. With such specialization (and expense) in optical printer optics what is the hope for the $50 50mm enlarger lens, optimized for <code>M = .1</code> and much too large a format? Not bad, provided the sharpest aperture is found and heeded and focusing technique is good. Also, for <code>M != 1</code> an asymmetrical lens should be mounted the right way, which is usually with its smaller glass facing the smaller image.</p>
<p>A very sharp cheap printer lens is the Canon Macrophoto 35mm f/2.8.</p> <p>A very sharp cheap printer lens is the Canon Macrophoto 35mm f/2.8.</p>
<p><a name="optical-zoom"></a></p> <p><a name="optical-zoom"></a></p>
<h2 id="optical-zoom">OPTICAL ZOOM</h2> <h2 id="optical-zoom">OPTICAL ZOOM</h2>
@ -305,7 +304,7 @@
<p>For picture taking the printer lens should be at whichever aperture gives the sharpest pictures. This is found in tests. If a lens must be stopped down past f/8 to reach optimum it is a terrible printer lens.</p> <p>For picture taking the printer lens should be at whichever aperture gives the sharpest pictures. This is found in tests. If a lens must be stopped down past f/8 to reach optimum it is a terrible printer lens.</p>
<p><a name="focusing"></a></p> <p><a name="focusing"></a></p>
<h2 id="focusing">FOCUSING</h2> <h2 id="focusing">FOCUSING</h2>
<p>Printer focusing procedure is different at different magnification. At 1:1 the camera, not the lens, is moved for focusing. Only at magnifications greater than about 1.4 is it better to move the lens for focusing. Near the 1:1 setup lens motion has no focusing effect. With the camera fixed in its 1:1 position lens motion: adjusts magnification between about M=.96 and M=1.04 (at f/5.6).</p> <p>Printer focusing procedure is different at different magnification. At 1:1 the camera, not the lens, is moved for focusing. Only at magnifications greater than about 1.4 is it better to move the lens for focusing. Near the 1:1 setup lens motion has no focusing effect. With the camera fixed in its 1:1 position lens motion adjusts magnification between about <code>M = .96</code> and <code>M = 1.04</code> (at f/5.6).</p>
<p><a name="focusing-aperature"></a></p> <p><a name="focusing-aperature"></a></p>
<h2 id="focusing-aperture">FOCUSING APERTURE</h2> <h2 id="focusing-aperture">FOCUSING APERTURE</h2>
<p>With all but the best optical printer lenses either (1) focus at the taking aperture or (2) focus at a larger aperture and then shift focus by a pre-established distance before taking. This “fudge-factor” is found in film tests.</p> <p>With all but the best optical printer lenses either (1) focus at the taking aperture or (2) focus at a larger aperture and then shift focus by a pre-established distance before taking. This “fudge-factor” is found in film tests.</p>
@ -331,8 +330,8 @@
<h2 id="x-y-adjustment">X-Y ADJUSTMENT</h2> <h2 id="x-y-adjustment">X-Y ADJUSTMENT</h2>
<p>Besides its to and fro movement the lens has lateral movements. These adjust the position of the original frame’s image on the print frame. For example, if the lens is raised a bit…</p> <p>Besides its to and fro movement the lens has lateral movements. These adjust the position of the original frame’s image on the print frame. For example, if the lens is raised a bit…</p>
<p><strong><img src="../img/image_5.svg" alt="Graphic depicting a lens’ central position between two frames demonstrating a rise adjusting framing" /></strong></p> <p><strong><img src="../img/image_5.svg" alt="Graphic depicting a lens’ central position between two frames demonstrating a rise adjusting framing" /></strong></p>
<p>At 1:1 moving the lens up a distance d raises the viewed field by twice d. Likewise for down, right, and left.</p> <p>At 1:1 moving the lens up a distance <code>d</code> raises the viewed field by twice <code>d</code>. Likewise for down, right, and left.</p>
<p>At <code>M &gt; 1</code> lateral adjustment effects a scan of the original frame. This is not geometrically equivalent to a pan, bad it been made in the original photography.</p> <p>At <code>M &gt; 1</code> lateral adjustment effects a scan of the original frame. This is not geometrically equivalent to a pan, had it been made in the original photography.</p>
<p>On simple optical printers the only lateral adjustment is of the lens (rather than the heavier camera or gate). This is geometrically adequate.</p> <p>On simple optical printers the only lateral adjustment is of the lens (rather than the heavier camera or gate). This is geometrically adequate.</p>
<p>But the J-K adjustments are even too flimsy for a lens. It helps, after they are set, to gently tap the lens, so it finds a stable position, and then to readjust if necessary, etc., etc.</p> <p>But the J-K adjustments are even too flimsy for a lens. It helps, after they are set, to gently tap the lens, so it finds a stable position, and then to readjust if necessary, etc., etc.</p>
<p><a name="exact-1-1"></a></p> <p><a name="exact-1-1"></a></p>
@ -341,10 +340,10 @@
<p><a name="aimframe"></a></p> <p><a name="aimframe"></a></p>
<h2 id="aimframe">AIMFRAME</h2> <h2 id="aimframe">AIMFRAME</h2>
<p>A special frame is made to guide the exact 1:1 setup. To make an “aimframe” use the optical printer camera (though not necessarily with the optical printer lens) to photograph a target which is especially drawn to contain details exactly coinciding, as seen through the camera eyepiece, with details permanently on the groundglass. The photograph made while the coincidence is seen is the aimframe.</p> <p>A special frame is made to guide the exact 1:1 setup. To make an “aimframe” use the optical printer camera (though not necessarily with the optical printer lens) to photograph a target which is especially drawn to contain details exactly coinciding, as seen through the camera eyepiece, with details permanently on the groundglass. The photograph made while the coincidence is seen is the aimframe.</p>
<p>Every groundglass has some permanent details, even if only its flaws. The field edge is a poor choice of detail if the mask is thick or if the eyepiece is aberrated at the edge. Two points of detail are enough for a well~aligned printer, three points for a suspect one.</p> <p>Every groundglass has some permanent details, even if only its flaws. The field edge is a poor choice of detail if the mask is thick or if the eyepiece is aberrated at the edge. Two points of detail are enough for a well-aligned printer, three points for a suspect one.</p>
<p>A reticle made on high resolution film may be attached to the groundglass to add details. Small patterns of concentric circles and other patterns which self-moiré are ideal. Also the aimframe can be a negative of the fine-patterned reticle.</p> <p>A reticle made on high resolution film may be attached to the groundglass to add details. Small patterns of concentric circles and other patterns which self-moiré are ideal. Also the aimframe can be a negative of the fine-patterned reticle.</p>
<p>For exact 1:1 setup, the aimframe film is registered in the printer gate and the printer camera and lens adjusted to achieve that same coincidence of details, as seen through the eyepiece. Focusing must be completed before the final adjustment to the aimframe. It is convenient to incorporate a focusing target in the aimframe.</p> <p>For exact 1:1 setup, the aimframe film is registered in the printer gate and the printer camera and lens adjusted to achieve that same coincidence of details, as seen through the eyepiece. Focusing must be completed before the final adjustment to the aimframe. It is convenient to incorporate a focusing target in the aimframe.</p>
<p>The aimframe has validity only for the camera in which it was made. It does not depend on the accuracy of the cameras reflex viewing system, only the stability of the system. Whenever there is doubt about the validity of the aimframe, such as after a camera repair or because of wear to the film, The old aimframe can be registered in the printer gate, aimed on, and photographed to make a newly valid aimframe.</p> <p>The aimframe has validity only for the camera in which it was made. It does not depend on the accuracy of the camera’s reflex viewing system, only the stability of the system. Whenever there is doubt about the validity of the aimframe, such as after a camera repair or because of wear to the film, The old aimframe can be registered in the printer gate, aimed on, and photographed to make a newly valid aimframe.</p>
<p>For rotoscoping with primitive contraptions, an aimframe may be projected and drawn. This drawing is later used to aim the camera (whose aimframe it was) when photographing the rotoscoped drawings.</p> <p>For rotoscoping with primitive contraptions, an aimframe may be projected and drawn. This drawing is later used to aim the camera (whose aimframe it was) when photographing the rotoscoped drawings.</p>
<p>The 1:1 accuracy of optical printing with aimframe setups is limited by</p> <p>The 1:1 accuracy of optical printing with aimframe setups is limited by</p>
<ol type="1"> <ol type="1">
@ -361,13 +360,13 @@
<p>If the camera which made the original film had a frameline much higher or lower than that of the printer camera, then the vertical adjustment of the lens should deviate from the aimframe setup, to compensate for this. Otherwise the print will have a very thick, or even a double frameline.</p> <p>If the camera which made the original film had a frameline much higher or lower than that of the printer camera, then the vertical adjustment of the lens should deviate from the aimframe setup, to compensate for this. Otherwise the print will have a very thick, or even a double frameline.</p>
<p>Sometimes the sole reason for optical printing is to adjust the height of the frameline of an original film shot with a wayward camera. Sometimes it is to simulate such film. Then the printer camera must have its frameline adjusted. For a Bolex this is a simple claw exchange (revertible).</p> <p>Sometimes the sole reason for optical printing is to adjust the height of the frameline of an original film shot with a wayward camera. Sometimes it is to simulate such film. Then the printer camera must have its frameline adjusted. For a Bolex this is a simple claw exchange (revertible).</p>
<p>To make a frameline adjustment, if the reflex viewfinder is well-set, then even if it does not view the full frame, the vertical adjustment can be made until the upper frameline just appears, then until the lower frameline just appears, and the two adjustments averaged.</p> <p>To make a frameline adjustment, if the reflex viewfinder is well-set, then even if it does not view the full frame, the vertical adjustment can be made until the upper frameline just appears, then until the lower frameline just appears, and the two adjustments averaged.</p>
<p>If the reflex viewfinder is untrustworthy, then a camera gate focuser can be used. Or this method: register in the printer gate a bipack of the original with any file shot in the printer camera. Determine how much vertical adjustment separates their framelines. Make that puch adjustment to the aimframe setup.</p> <p>If the reflex viewfinder is untrustworthy, then a camera gate focuser can be used. Or this method: register in the printer gate a bipack of the original with any file shot in the printer camera. Determine how much vertical adjustment separates their framelines. Make that much adjustment to the aimframe setup.</p>
<p>The framelines of the original can always be eliminated from the print by setting the magnification slightly greater than 1.</p> <p>The framelines of the original can always be eliminated from the print by setting the magnification slightly greater than 1.</p>
<p><a name="emulsion-position"></a></p> <p><a name="emulsion-position"></a></p>
<h2 id="emulsion-position">EMULSION POSITION</h2> <h2 id="emulsion-position">EMULSION POSITION</h2>
<p>A priori, a film of an alphabet could be any of these eight ways.</p> <p>A priori, a film of an alphabet could be any of these eight ways.</p>
<p><strong><img src="../img/image_6.svg" alt="Graphic depicting eight strips of film with letters F and G oriented and labelled" /></strong></p> <p><strong><img src="../img/image_6.svg" alt="Graphic depicting eight strips of film with letters F and G oriented and labelled" /></strong></p>
<p>Each sketch shows emulsion facing out. For double perf film there are only four ways. The a and b ways become the same.</p> <p>Each sketch shows emulsion facing out. For double perf film there are only four ways. The <code>a</code> and <code>b</code> ways become the same.</p>
<p>Camera original is (IIIa).</p> <p>Camera original is (IIIa).</p>
<p>A contact print from camera original is (Ib). A contact print from a contact print from camera original is (IIIa) again. Etc.</p> <p>A contact print from camera original is (Ib). A contact print from a contact print from camera original is (IIIa) again. Etc.</p>
<p>All the others are shams–either optical printing errors or else films of alphabets somehow reversed.</p> <p>All the others are shams–either optical printing errors or else films of alphabets somehow reversed.</p>
@ -395,9 +394,14 @@
<p>To slow motion to 3/4 speed (as is required when original shot at 18fps is to be made into a 24fps print) it is usual to print every third frame twice. ABCDEFGHI… becomes ABCCDEFFGHII… . The micro-freezes, just two frames long, coming every 1/6 second, are perceived through their rhythm. This can be avoided by randomizing the frames to be doubled while still choosing one frame from each three of the original.</p> <p>To slow motion to 3/4 speed (as is required when original shot at 18fps is to be made into a 24fps print) it is usual to print every third frame twice. ABCDEFGHI… becomes ABCCDEFFGHII… . The micro-freezes, just two frames long, coming every 1/6 second, are perceived through their rhythm. This can be avoided by randomizing the frames to be doubled while still choosing one frame from each three of the original.</p>
<p><a name="diffusers"></a></p> <p><a name="diffusers"></a></p>
<h2 id="diffusers">DIFFUSERS</h2> <h2 id="diffusers">DIFFUSERS</h2>
<p>For poorly designed condenser systems a diffuser will even the illumination over the frame. Other than for this, diffusers are located immediately behind the original film to alter image quality in several ways: 1. reduce the appearance of scratches on the film base; 2. soften the appearance of grain, and without reducing resolution <em>per se</em>, reduce sharpness; 3. reduce the apparent oontrast of B&amp;W originals, approximating the tonality in contact printing.</p> <p>For poorly designed condenser systems a diffuser will even the illumination over the frame. Other than for this, diffusers are located immediately behind the original film to alter image quality in several ways:</p>
<ol type="1">
<li>reduce the appearance of scratches on the film base;</li>
<li>soften the appearance of grain, and without reducing resolution <em>per se</em>, reduce sharpness;</li>
<li>reduce the apparent contrast of B&amp;W originals, approximating the tonality in contact printing.</li>
</ol>
<p>Opal glass, a more extreme diffuser than groundglass, is more effective in each of the three ways.</p> <p>Opal glass, a more extreme diffuser than groundglass, is more effective in each of the three ways.</p>
<p>An opal glase oan reduce exposure by 4 or even more stops. An accidental or for;otten opal glass can devastate an exposure!</p> <p>An opal glass can reduce exposure by 4 or even more stops. An accidental or forgotten opal glass can devastate an exposure!</p>
<p><a name="uv-filter"></a></p> <p><a name="uv-filter"></a></p>
<h2 id="uv-filter">UV FILTER</h2> <h2 id="uv-filter">UV FILTER</h2>
<p>A filter which absorbs the ultraviolet, such as Wratten 2B or 2E improves sharpness with almost all lenses.</p> <p>A filter which absorbs the ultraviolet, such as Wratten 2B or 2E improves sharpness with almost all lenses.</p>
@ -413,10 +417,10 @@
<p>Printing B&amp;W to B&amp;W with a non-apochromatic lens, a green filter can improve sharpness.</p> <p>Printing B&amp;W to B&amp;W with a non-apochromatic lens, a green filter can improve sharpness.</p>
<p><a name="filter-location"></a></p> <p><a name="filter-location"></a></p>
<h2 id="filter-location">FILTER LOCATION</h2> <h2 id="filter-location">FILTER LOCATION</h2>
<p>The spectral effect of a filter on the photography is the same wherever it is located between the lamp and the rawatock. The optical effect of a filter can’t be good, so it ought to be located on the illumination side of the original rather than on the image-formation side. (There, flaws in filters are harmless. A color filter may even be perforated to reduce its effective saturation.)</p> <p>The spectral effect of a filter on the photography is the same wherever it is located between the lamp and the rawstock. The optical effect of a filter can’t be good, so it ought to be located on the illumination side of the original rather than on the image-formation side. (There, flaws in filters are harmless. A color filter may even be perforated to reduce its effective saturation.)</p>
<p><a name="exposure"></a></p> <p><a name="exposure"></a></p>
<h2 id="exposure">EXPOSURE</h2> <h2 id="exposure">EXPOSURE</h2>
<p>In optical printing as in original photography, the exposure is adjustable, and a necessary consideration. But there is a difference. The natural scene may exhibit an immense brightness range, from the brightest light sources (and secondary sources–reflections) to the darkest light sinks. The film original is limited in brightness range, between the clear of the base and the maximum density of the emulsion. This could be an 11 atop range for some color reversal films, but only about 6 stops for a negative original.</p> <p>In optical printing as in original photography, the exposure is adjustable, and a necessary consideration. But there is a difference. The natural scene may exhibit an immense brightness range, from the brightest light sources (and secondary sources–reflections) to the darkest light sinks. The film original is limited in brightness range, between the clear of the base and the maximum density of the emulsion. This could be an 11 stop range for some color reversal films, but only about 6 stops for a negative original.</p>
<p>The exposure problem in original photography is to decide what portion of the immense brightness range to capture on the film. The exposure problem in optical printing is to decide how to capture on the print film the whole of the original image range.</p> <p>The exposure problem in original photography is to decide what portion of the immense brightness range to capture on the film. The exposure problem in optical printing is to decide how to capture on the print film the whole of the original image range.</p>
<p><a name="exposure-adjusters"></a></p> <p><a name="exposure-adjusters"></a></p>
<h2 id="exposure-adjusters">EXPOSURE ADJUSTERS</h2> <h2 id="exposure-adjusters">EXPOSURE ADJUSTERS</h2>
@ -424,10 +428,10 @@
<p>With the variable shutter the shutter speed (the time the light strikes a point in the frame) may be adjusted although the printer camera runs at just one speed. Exposure can be adjusted over several stops with the variable shutter. Brevity is limited by the shutter mechanics which must give equal even exposures at the smallest shutter angles.</p> <p>With the variable shutter the shutter speed (the time the light strikes a point in the frame) may be adjusted although the printer camera runs at just one speed. Exposure can be adjusted over several stops with the variable shutter. Brevity is limited by the shutter mechanics which must give equal even exposures at the smallest shutter angles.</p>
<p>To cut exposure by 1 stop using the variable shutter, halve the shutter angle. To cut another stop, halve it again.</p> <p>To cut exposure by 1 stop using the variable shutter, halve the shutter angle. To cut another stop, halve it again.</p>
<p>Using the variable shutter for exposure adjustment makes its use for fades or dissolves inconvenient.</p> <p>Using the variable shutter for exposure adjustment makes its use for fades or dissolves inconvenient.</p>
<p><strong>LENS APERTURE</strong> - This is a silly way to adjust exposure. Changing lens aperture changes picture sharpness. Except for fine expoeure adjustments (+/1 1/2 stop) the lens is best left at its sharpest opening.</p> <p><strong>LENS APERTURE</strong> - This is a silly way to adjust exposure. Changing lens aperture changes picture sharpness. Except for fine exposure adjustments (± 1/2 stop) the lens is best left at its sharpest opening.</p>
<p>(For exposure testing and other dirty work, lens aperture is a handy exposure adjuster.)</p> <p>(For exposure testing and other dirty work, lens aperture is a handy exposure adjuster.)</p>
<p><strong>LAMP VOLTAGE</strong> - This is the classical way to adjust exposure for B&amp;W printing. But it introduces color changes. Also, modern halogen lamps lose life at prolonged low voltages. Voltage adjustment is a practical means for fine exposure adjustment.</p> <p><strong>LAMP VOLTAGE</strong> - This is the classical way to adjust exposure for B&amp;W printing. But it introduces color changes. Also, modern halogen lamps lose life at prolonged low voltages. Voltage adjustment is a practical means for fine exposure adjustment.</p>
<p>Dropping the voltage 10% reduces the light about t stop while changing the color about <code>CCO5Y+CCO2M</code>.</p> <p>Dropping the voltage 10% reduces the light about 1/2 stop while changing the color about <code>CCO5Y+CCO2M</code>.</p>
<p><strong>POLARIZERS</strong> - Two polarizers, one rotatable, is a cute way to adjust exposure. But sheet polarizers get hot and have short lives in the optical printer. Only very expensive ones can maintain color neutrality over a 10 stop adjustment range, and it is sad to fry them.</p> <p><strong>POLARIZERS</strong> - Two polarizers, one rotatable, is a cute way to adjust exposure. But sheet polarizers get hot and have short lives in the optical printer. Only very expensive ones can maintain color neutrality over a 10 stop adjustment range, and it is sad to fry them.</p>
<p><strong>ND FILTERS</strong> - These grey filters are the preferred way to adjust exposure.</p> <p><strong>ND FILTERS</strong> - These grey filters are the preferred way to adjust exposure.</p>
<p>.30 of Neutral Density equals one stop.</p> <p>.30 of Neutral Density equals one stop.</p>
@ -456,21 +460,21 @@
<p><a name="film-speed"></a></p> <p><a name="film-speed"></a></p>
<h2 id="film-speed">FILM SPEED</h2> <h2 id="film-speed">FILM SPEED</h2>
<p>ASA and related values are specialized to original picture taking and are not quite appropriate to optical printer applications. The values are informative for comparison of similar stocks. For many printing films ASA and related values are undefinable.</p> <p>ASA and related values are specialized to original picture taking and are not quite appropriate to optical printer applications. The values are informative for comparison of similar stocks. For many printing films ASA and related values are undefinable.</p>
<p>The optical printer will have exposure standards unto itself, determined by testing. Once it is known how to beat expose, a certain original onto a certain print film, good estimates can be made for similar originals or similar print films.</p> <p>The optical printer will have exposure standards unto itself, determined by testing. Once it is known how to best expose a certain original onto a certain print film, good estimates can be made for similar originals or similar print films.</p>
<p><a name="right-exposure"></a></p> <p><a name="right-exposure"></a></p>
<h2 id="right-exposure">RIGHT EXPOSURE</h2> <h2 id="right-exposure">RIGHT EXPOSURE</h2>
<p>Working in reversal there is a temptation to want the optical print to match the original. Resist this temptation! You want the optical print that produces the best release print.</p> <p>Working in reversal there is a temptation to want the optical print to match the original. Resist this temptation! You want the optical print that produces the best release print.</p>
<p>(Even if the optical print must be intercut with the original, so that the two must produce matching release print, it doesn’t follow that the two must match, and they shouldn’t.)</p> <p>(Even if the optical print must be intercut with the original, so that the two must produce matching release print, it doesn’t follow that the two must match, and they shouldn’t.)</p>
<p>Starting from reversal camera original the best reversal optical print is typically a little (about <code>ND.20</code>) darker than the original. This avoids the print film’s toe. The best reversal optical print of this will match it. And so on.</p> <p>Starting from reversal camera original the best reversal optical print is typically a little (about <code>ND.20</code>) darker than the original. This avoids the print film’s toe. The best reversal optical print of this will match it. And so on.</p>
<p>Starting from negative camera Original the best interpositive print has some density in the highlights. The beat internegative is a little darker than the original negative. A further interpositive would best match the first one, etc.</p> <p>Starting from negative camera original the best interpositive print has some density in the highlights. The best internegative is a little darker than the original negative. A further interpositive would best match the first one, etc.</p>
<p><a name="generations"></a></p> <p><a name="generations"></a></p>
<h2 id="generations">GENERATIONS</h2> <h2 id="generations">GENERATIONS</h2>
<p>Gammas multiply. For example, a gamma 1.5 original printed onto gamma 2 stock resembles a gamma 3 original.</p> <p>Gammas multiply. For example, a gamma 1.5 original printed onto gamma 2 stock resembles a gamma 3 original.</p>
<p>In many-generation pictorial optical printing a chain of gamma 1 steps results in unchanging picture contrast. 7399 and CRI are gamma 1 color reversal stocks. 7243 is a gamma 1 color negative stock. PXR and 7361 are gamma 1 B&amp;W reversal stocks. 7235 is a gamma 1 B&amp;w negative stock.</p> <p>In many-generation pictorial optical printing a chain of gamma 1 steps results in unchanging picture contrast. 7399 and CRI are gamma 1 color reversal stocks. 7243 is a gamma 1 color negative stock. PXR and 7361 are gamma 1 B&amp;W reversal stocks. 7235 is a gamma 1 B&amp;w negative stock.</p>
<p>For B&amp;W negative there is the option of alternating gammas above and below 1–7366 with gamma 1.4 and 7234 with gamma .7–and multiply out to 1.</p> <p>For B&amp;W negative there is the option of alternating gammas above and below 1–7366 with gamma 1.4 and 7234 with gamma .7–and multiply out to 1.</p>
<p>There are no available reversal stocks with Gamma less than 1.</p> <p>There are no available reversal stocks with gamma less than 1.</p>
<p>For color reversal ECO, until its disappearance in 1985, was a favorite gamma 1 camera stock and ECO–ECO–ECO–etc. was the classical printing scheme. ECO–7399–7399–etc. was a similar, possibly better scheme. For each, only the release print would be on higher gamma stock. No present color reversal scheme has that advantage. Higher gamma original VNF–7399–7399–etc. is a printing scheme. For this, the release print too will be on 7399. Original Kodachrome follows the VNF scheme.</p> <p>For color reversal ECO, until its disappearance in 1985, was a favorite gamma 1 camera stock and ECO–ECO–ECO–etc. was the classical printing scheme. ECO–7399–7399–etc. was a similar, possibly better scheme. For each, only the release print would be on higher gamma stock. No present color reversal scheme has that advantage. Higher gamma original VNF–7399–7399–etc. is a printing scheme. For this, the release print too will be on 7399. Original Kodachrome follows the VNF scheme.</p>
<p>7399 stock misbehaves with exposure times longer than about -1 second.</p> <p>7399 stock misbehaves with exposure times longer than about .1 second.</p>
<p>For B&amp;W reversal PXR–PXR–PXR–etc. is the classical printing scheme. PXR–7361–7361–etc. is a similar, slightly better scheme. For each, unless an opal diffuser is used the effective gamma is much greater than 1.</p> <p>For B&amp;W reversal PXR–PXR–PXR–etc. is the classical printing scheme. PXR–7361–7361–etc. is a similar, slightly better scheme. For each, unless an opal diffuser is used the effective gamma is much greater than 1.</p>
<p>For color negative ECN–7243–7243–etc. is the classical printing scheme. The alternating positive and negative pictures allow different manipulations. Optical printing from picture negative requires unusual cleanliness, to avoid white specks in the final image. A good strategy is to make the odd printing steps quick and simple, perhaps even contact printed.</p> <p>For color negative ECN–7243–7243–etc. is the classical printing scheme. The alternating positive and negative pictures allow different manipulations. Optical printing from picture negative requires unusual cleanliness, to avoid white specks in the final image. A good strategy is to make the odd printing steps quick and simple, perhaps even contact printed.</p>
<p>The shortcut scheme for color negative ECN–CRI–CRI–etc. comprises only picture negatives.</p> <p>The shortcut scheme for color negative ECN–CRI–CRI–etc. comprises only picture negatives.</p>
@ -481,7 +485,7 @@
<p>Optical printing with the best lenses onto relatively thick emulsion print films may be sharper than contact printing. Generally optical printing isn’t as sharp. Picture degradation from generation to generation could be avoided by making the pictures very large, or by digitalizing them. But in this medium the original, intermediate, and final pictures are all of the same size, made in similar ways, of similar materials. Besides the practical economy, there is conceptual economy in this. Intuitions transfer easily from one formally similar picture phase to another. Thus making the generations the same makes them different. This is the paradox, or the folly, of optical printing.</p> <p>Optical printing with the best lenses onto relatively thick emulsion print films may be sharper than contact printing. Generally optical printing isn’t as sharp. Picture degradation from generation to generation could be avoided by making the pictures very large, or by digitalizing them. But in this medium the original, intermediate, and final pictures are all of the same size, made in similar ways, of similar materials. Besides the practical economy, there is conceptual economy in this. Intuitions transfer easily from one formally similar picture phase to another. Thus making the generations the same makes them different. This is the paradox, or the folly, of optical printing.</p>
<p><a name="bellows-formula"></a></p> <p><a name="bellows-formula"></a></p>
<h2 id="bellows-formula">BELLOWS FORMULA</h2> <h2 id="bellows-formula">BELLOWS FORMULA</h2>
<p>Exposure way change with magnification. A “bellows formula” works for most printer lenses and most illumination systems. It prescribes…</p> <p>Exposure may change with magnification. A “bellows formula” works for most printer lenses and most illumination systems. It prescribes…</p>
<table> <table>
<thead> <thead>
<tr class="header"> <tr class="header">
@ -559,16 +563,15 @@
<p>Although it is marked in stops, it is configured for angular callibration. Open is 130°. Just closed is 0°. Midway is 65°. Percentage of full can be substituted for degrees. Fine callibration should not be attempted for there is play in the mechanism.</p> <p>Although it is marked in stops, it is configured for angular callibration. Open is 130°. Just closed is 0°. Midway is 65°. Percentage of full can be substituted for degrees. Fine callibration should not be attempted for there is play in the mechanism.</p>
<p><a name="linear-fade"></a></p> <p><a name="linear-fade"></a></p>
<h2 id="linear-fade">LINEAR FADE</h2> <h2 id="linear-fade">LINEAR FADE</h2>
<p>The linear fadeout, compared with the log fadeout of the sane length, starts slower and finishes faster.</p> <p>The linear fadeout, compared with the log fadeout of the same length, starts slower and finishes faster.</p>
<p>With a variable shutter a linear fadeout from a positive original 16 made by subtracting each new frame a certain angles. For simplicity, take a linear fadeout to be complete at O°. For example, with a 180° shutter a 30 frame linear fade changes 6° each frame.</p> <p>With a variable shutter a linear fadeout from a positive original is made by subtracting each new frame a certain angles. For simplicity, take a linear fadeout to be complete at 0°. For example, with a 180° shutter a 30 frame linear fade changes 6° each frame.</p>
<p>ND filters can be used to make a linear fade. The fade is planned as if for a variable shutter and then ND equivalents are found in Chart C.</p> <p>ND filters can be used to make a linear fade. The fade is planned as if for a variable shutter and then ND equivalents are found in Chart C.</p>
<p><a name="other-fades"></a></p> <p><a name="other-fades"></a></p>
<h2 id="other-fades">OTHER FADES</h2> <h2 id="other-fades">OTHER FADES</h2>
<p>Any gradual transition between full exposure and black is an exposure fade. The “look”, and perhaps the “meaning”, of a fade depends on how the exposure changes with the frames.</p> <p>Any gradual transition between full exposure and black is an exposure fade. The “look”, and perhaps the “meaning”, of a fade depends on how the exposure changes with the frames.</p>
<p><a name="fades-in-original"></a></p> <p><a name="fades-in-original"></a></p>
<h2 id="fades-in-original">FADES IN ORIGINAL</h2> <h2 id="fades-in-original">FADES IN ORIGINAL</h2>
<p>A fade made from a scene looks distinctly different from one made from a film image of the scene if the scene containga bright highlights. Made from the scene, the highlights shine on when the remainder of the scene is practically black. Made from the film, the highlights follow the other light parts of the picture.</p> <p>A fade made from a scene looks distinctly different from one made from a film image of the scene if the scene contains bright highlights. Made from the scene, the highlights shine on when the remainder of the scene is practically black. Made from the film, the highlights follow the other light parts of the picture.</p>
<p><a name="chart-c"></a></p> <p><a name="chart-c"></a></p>
<h3 id="neutral-density-and-equivalent-shutter-angle">NEUTRAL DENSITY AND EQUIVALENT SHUTTER ANGLE</h3> <h3 id="neutral-density-and-equivalent-shutter-angle">NEUTRAL DENSITY AND EQUIVALENT SHUTTER ANGLE</h3>
<p>CHART C</p> <p>CHART C</p>
@ -627,7 +630,7 @@
<tr class="odd"> <tr class="odd">
<td>.30</td> <td>.30</td>
<td>50.1%</td> <td>50.1%</td>
<td>95°</td> <td>85°</td>
<td>____</td> <td>____</td>
</tr> </tr>
<tr class="even"> <tr class="even">
@ -668,7 +671,7 @@
</tr> </tr>
<tr class="even"> <tr class="even">
<td>.65</td> <td>.65</td>
<td>22.48</td> <td>22.4%</td>
<td>38°</td> <td>38°</td>
<td>____</td> <td>____</td>
</tr> </tr>
@ -759,7 +762,7 @@
<tr class="odd"> <tr class="odd">
<td>1.40</td> <td>1.40</td>
<td>3.98%</td> <td>3.98%</td>
<td>6.8</td> <td>6.8°</td>
<td>____</td> <td>____</td>
</tr> </tr>
<tr class="even"> <tr class="even">
@ -776,7 +779,7 @@
</tr> </tr>
<tr class="even"> <tr class="even">
<td>1.55</td> <td>1.55</td>
<td>2.52%</td> <td>2.82%</td>
<td>4.8°</td> <td>4.8°</td>
<td>____</td> <td>____</td>
</tr> </tr>
@ -938,7 +941,6 @@
</tr> </tr>
</tbody> </tbody>
</table> </table>
<p>**Refer to this chart when planning linear fades and dissolves**</p> <p>**Refer to this chart when planning linear fades and dissolves**</p>
<h3 id="equivalent-shutter-openings">Equivalent Shutter Openings</h3> <h3 id="equivalent-shutter-openings">Equivalent Shutter Openings</h3>
<table> <table>
@ -962,7 +964,7 @@
<tr class="even"> <tr class="even">
<td>.05</td> <td>.05</td>
<td>89.1</td> <td>89.1</td>
<td>140</td> <td>160</td>
<td>115</td> <td>115</td>
<td>209</td> <td>209</td>
</tr> </tr>
@ -1005,7 +1007,7 @@
<td>.35</td> <td>.35</td>
<td>44.7</td> <td>44.7</td>
<td>80</td> <td>80</td>
<td>53</td> <td>58</td>
<td>105</td> <td>105</td>
</tr> </tr>
<tr class="odd"> <tr class="odd">
@ -1156,7 +1158,7 @@
<td>9</td> <td>9</td>
</tr> </tr>
<tr class="even"> <tr class="even">
<td>1,45</td> <td>1.45</td>
<td>3.55</td> <td>3.55</td>
<td>6.4</td> <td>6.4</td>
<td>5</td> <td>5</td>
@ -1171,52 +1173,52 @@
</tr> </tr>
</tbody> </tbody>
</table> </table>
<p><a name="image-superposition"></a></p> <p><a name="image-superposition"></a></p>
<h2 id="image-superposition">IMAGE SUPERPOSITION</h2> <h2 id="image-superposition">IMAGE SUPERPOSITION</h2>
<p>In an overall combination of two images, the two can infuse each other as lightness or as darkness, or they can be slapped onto each other. There are three basic types of image superposition, named according to how they are made.</p> <p>In an overall combination of two images, the two can infuse each other as lightness or as darkness, or they can be slapped onto each other. There are three basic types of image superposition, named according to how they are made.</p>
<p>Pictures A &amp; B combined by…</p> <p>Pictures A &amp; B combined by…</p>
<ol type="1"> <ol type="1">
<li><span class="underline">Double exposure from positives.</span> The print film is eared twice, once from A’s positive, once from B’s positive.</li> <li><span class="underline">Double exposure from positives.</span> The print film is exposed twice, once from A’s positive, once from B’s positive.</li>
<li><span class="underline">Double exposure from negatives.</span> The print film is exposed twice, once from A’s negative, once from B’s negative.</li> <li><span class="underline">Double exposure from negatives.</span> The print film is exposed twice, once from A’s negative, once from B’s negative.</li>
<li><span class="underline">Bipack.</span> Two films, either A’s and B’s positives, or else A’s and B’s negatives, are inserted together in the printer gate. The print film is exposed once, from this pair.</li> <li><span class="underline">Bipack.</span> Two films, either A’s and B’s positives, or else A’s and B’s negatives, are inserted together in the printer gate. The print film is exposed once, from this pair.</li>
</ol> </ol>
<p>The print film is unspecified. It is in the final positive print that the three types of combination are compared, and they look very different. For B&amp;W the differences can be described by how tones combine.</p> <p>The print film is unspecified. It is in the final positive print that the three types of combination are compared, and they look very different. For B&amp;W the differences can be described by how tones combine.</p>
<p>With (1), lightness dominates. Where one tone combines with another tone the result is nearly the lighter of the two tones.</p> <p>With (1), lightness dominates. Where one tone combines with another tone the result is nearly the lighter of the two tones.</p>
<p>With (2), darkness dominates. The result is nearly the darker of the two tones.</p> <p>With (2), darkness dominates. The result is nearly the darker of the two tones.</p>
<p>With (3), there is contrastification which complicates the tone combination. If a bipack is examined ray (unprinted) wherever both images are clear the bipack is clear. Wherever either image is black the bipack is at least that black. Wherever both images are black the bipack is doubly black. The bipack, which appears dark, has a tonal range doubling that of the single images. The bipack is unprintable in toto.</p> <p>With (3), there is contrastification which complicates the tone combination. If a bipack is examined raw (unprinted) wherever both images are clear the bipack is clear. Wherever either image is black the bipack is at least that black. Wherever both images are black the bipack is doubly black. The bipack, which appears dark, has a tonal range doubling that of the single images. The bipack is unprintable in toto.</p>
<p>To abstract a picture from the unprintable bipack printing exposure is typically increased 1-4 stops. With 4 stops increase, where clear and black coincide prints as a dark grey would—-not a clear domination of either lightness or darkness. With 2 stops increase there is darkness domination.</p> <p>To abstract a picture from the unprintable bipack printing exposure is typically increased 1-4 stops. With 4 stops increase, where clear and black coincide prints as a dark grey would—-not a clear domination of either lightness or darkness. With 2 stops increase there is darkness domination.</p>
<p><a name="gamma-and-bipack"></a></p> <p><a name="gamma-and-bipack"></a></p>
<h2 id="gamma-bipack">GAMMA &amp; BIPACK</h2> <h2 id="gamma-bipack">GAMMA &amp; BIPACK</h2>
<p>If the bipack is printed onto gamma $ material, to reduce the contrast to normal, it is a true tonal blender, without dominance, of the two images. As the graphs below show, the gamma 1/2 bipack is the mean between the type (1) and type (2) double exposures.</p> <p>If the bipack is printed onto gamma 1/2 material, to reduce the contrast to normal, it is a true tonal blender, without dominance, of the two images. As the graphs below show, the gamma 1/2 bipack is the mean between the type (1) and type (2) double exposures.</p>
<p><a name="incidentally"></a></p> <p><a name="incidentally"></a></p>
<h2 id="incidentally">INCIDENTALLY</h2> <h2 id="incidentally">INCIDENTALLY</h2>
<p>A type (3) of a type (1) and a type (2) is just a type (3) again.</p> <p>A type (3) of a type (1) and a type (2) is just a type (3) again.</p>
<p>Four idealized graphs summarize the three basic types of superposition and the gamma 1/2 bipack.</p> <p>Four idealized graphs summarize the three basic types of superposition and the gamma 1/2 bipack.</p>
<p>Example:</p> <p>Example:</p>
<blockquote> <blockquote>
<p>4 has density .75 and B has density 1.75 in one place. From the first graph, the double exposure from positives has density about 1.0 in that place.</p> <p><code>A</code> has density .75 and <code>B</code> has density 1.75 in one place. From the first graph, the double exposure from positives has density about 1.0 in that place.</p>
</blockquote> </blockquote>
<p><strong><img src="../img/image_8.svg" alt="Graphics depicting DOUBLE EXPOSURE FROM POS’S, BIPACK (1.0 COMPENS) DOUBLE EXPOSURE FROM NEGS and GAMMA 1/2 BIPACK" /></strong></p> <p><strong><img src="../img/image_8.svg" alt="Graphics depicting DOUBLE EXPOSURE FROM POS’S, BIPACK (1.0 COMPENS) DOUBLE EXPOSURE FROM NEGS and GAMMA 1/2 BIPACK" /></strong></p>
<p>For a double exposure it doesn’t matter which exposure is first, or what time separates the two. In some multi-head optical printers, using a beam-splitter, the two exposures are simultaneous. Either way, the two films can be independently adjusted for exposure, filtered, etc.</p> <p>For a double exposure it doesn’t matter which exposure is first, or what time separates the two. In some multi-head optical printers, using a beam-splitter, the two exposures are simultaneous. Either way, the two films can be independently adjusted for exposure, filtered, etc.</p>
<p>For a bipack it doesn’t matter which film is in front. Also the two may be optically instead of mechanically bipacked. In some multi-head optical printers the films are in separate gates, ones projection becoming the other’s illumination. In a simple printer one film may be in the gate and the other in the camera, in front of the print film. Any way, the two films ehare one exposure adjustment and filtration.</p> <p>For a bipack it doesn’t matter which film is in front. Also the two may be optically instead of mechanically bipacked. In some multi-head optical printers the films are in separate gates, ones projection becoming the other’s illumination. In a simple printer one film may be in the gate and the other in the camera, in front of the print film. Any way, the two films share one exposure adjustment and filtration.</p>
<p>When films will be physically bipacked they should first be wiped with a lubricating film cleaner. This is good practice for all optical printing when delicate originals receive heavy handling.</p> <p>When films will be physically bipacked they should first be wiped with a lubricating film cleaner. This is good practice for all optical printing when delicate originals receive heavy handling.</p>
<p><a name="exposure-compensation"></a></p> <p><a name="exposure-compensation"></a></p>
<h2 id="exposure-compensation">EXPOSURE COMPENSATION</h2> <h2 id="exposure-compensation">EXPOSURE COMPENSATION</h2>
<p>For superpositions from random pictorial originals:</p> <p>For superpositions from random pictorial originals:</p>
<p>For double exposures, the typical exposure adjustment is one stop of decrease from normal, during each exposure.</p> <p>For double exposures, the typical exposure adjustment is one stop of decrease from normal, during each exposure.</p>
<blockquote> <blockquote>
<p>With this adjustment a double exposure of picture A with picture A ie the same as a single normal exposure of A.</p> <p>With this adjustment a double exposure of picture A with picture A is the same as a single normal exposure of A.</p>
</blockquote> </blockquote>
<p>For bipacks there is no recipe. Exposure adjustment is extremely dependent on which tones coincide with which. The adjustment is an increase from normal. In ignorance of the originals (why?) and ignorance of the intentions (why?) guess 2 1/2 stops increase.</p> <p>For bipacks there is no recipe. Exposure adjustment is extremely dependent on which tones coincide with which. The adjustment is an increase from normal. In ignorance of the originals (why?) and ignorance of the intentions (why?) guess 2 1/2 stops increase.</p>
<blockquote> <blockquote>
<p>No exposure adjustment can make a bipack of picture A with picture A the same as picture. A printed the same. But a gamma 1/2 bipack of picture A with picture A is the same as picture.</p> <p>No exposure adjustment can make a bipack of picture A with picture A the same as picture A printed the same. But a gamma 1/2 bipack of picture A with picture A is the same as picture A.</p>
</blockquote> </blockquote>
<p><a name="special-originals"></a></p> <p><a name="special-originals"></a></p>
<h2 id="special-originals">SPECIAL ORIGINALS</h2> <h2 id="special-originals">SPECIAL ORIGINALS</h2>
<p>For superpositions not from random pictorial originals tones might not combine at all. One image might fall on the other’s black, or clear, and exposure compensation is different, perhaps unnecessary.</p> <p>For superpositions not from random pictorial originals tones might not combine at all. One image might fall on the other’s black, or clear, and exposure compensation is different, perhaps unnecessary.</p>
<p>With special, rigged, originale superposition is not image combination in the earlier sense but image apportionment–implantings and supplantings.</p> <p>With special, rigged, originals superposition is not image combination in the earlier sense but image apportionment–implantings and supplantings.</p>
<p>The rules of tone combination still apply, but trivially, and a simpler logic prevails. Double exposing from positives, where one image is black the other image appears, unaffected by the double exposure. Where one image is very light it appears, hardly affected by the double exposure.</p> <p>The rules of tone combination still apply, but trivially, and a simpler logic prevails.</p>
<p>Double exposing from positives, where one image is black the other image appears, unaffected by the double exposure. Where one image is very light it appears, hardly affected by the double exposure.</p>
<p>Double exposing from negatives, where one image (the picture, not the film) is clear the other image appears, unaffected by the double exposure.</p> <p>Double exposing from negatives, where one image (the picture, not the film) is clear the other image appears, unaffected by the double exposure.</p>
<p>Bipacking, where one image is any even tone, the other image appears, unaffected except for brightness. The clear parts of one film are windows for the other film. But it is possible, with enough extra exposure, to force one image through the blackened window of the other.</p> <p>Bipacking, where one image is any even tone, the other image appears, unaffected except for brightness. The clear parts of one film are windows for the other film. But it is possible, with enough extra exposure, to force one image through the blackened window of the other.</p>
<p>The most extreme cases of rigged originals involve high contrast masks, discussed below.</p> <p>The most extreme cases of rigged originals involve high contrast masks, discussed below.</p>
@ -1248,30 +1250,41 @@
<p><a name="color-image-superposition"></a></p> <p><a name="color-image-superposition"></a></p>
<h2 id="color-image-superposition">COLOR IMAGE SUPERPOSITION</h2> <h2 id="color-image-superposition">COLOR IMAGE SUPERPOSITION</h2>
<p>There are the same three basic types.</p> <p>There are the same three basic types.</p>
<p>Double exposure from positives gives additive color mixture. Bipacking gives so-called subtractive color mixture. When bipacking color negatives the extra orange mask should be neutralized by filtering.)</p> <p>Double exposure from positives gives additive color mixture. Bipacking gives so-called subtractive color mixture. (When bipacking color negatives the extra orange mask should be neutralized by filtering.)</p>
<p>Double exposure from negatives gives something else.</p> <p>Double exposure from negatives gives something else.</p>
<p>For greys in the two images, combination is as for B&amp;W. But for colors, not only are new colors produced but apparent brightnesses do not combine quite the same ae for B&amp;W.</p> <p>For greys in the two images, combination is as for B&amp;W. But for colors, not only are new colors produced but apparent brightnesses do not combine quite the same as for B&amp;W.</p>
<p>The dyes in Wratten CC filters Y, M, C are similar to those in color films. Film colors can be simulated by packs of these filters and much can be learned about film color manipulation from familiarity with the filters and their combinations.</p> <p>The dyes in Wratten CC filters Y, M, C are similar to those in color films. Film colors can be simulated by packs of these filters and much can be learned about film color manipulation from familiarity with the filters and their combinations.</p>
<p>Example 1:</p> <p>Example 1:</p>
<blockquote> <blockquote>
<p>Image &amp; is orange (<code>CC200Y</code>+<code>CC100M</code>) Image B ts blue (<code>CC100M</code>+<code>CC200C</code>)</p> <p>Image A is orange (<code>CC200Y</code>+<code>CC100M</code>)</p>
<p>Image B is blue (<code>CC100M</code>+<code>CC200C</code>)</p>
</blockquote> </blockquote>
<blockquote> <blockquote>
<p>Double exposure from positives gives a raspberry color (<code>CC7OM</code>+<code>ND.30</code>) Double exposure from negatives gives a fairly dark greyish green (<code>CC7OY</code>+<code>CC70C</code>+<code>ND1.00</code>) Bipack, with 3 stop exposure compensation, gives a middle grey (<code>ND1.10</code>)</p> <p>Double exposure from positives gives a raspberry color (<code>CC7OM</code>+<code>ND.30</code>)</p>
<p>Double exposure from negatives gives a fairly dark greyish green (<code>CC7OY</code>+<code>CC70C</code>+<code>ND1.00</code>)</p>
</blockquote>
<blockquote>
<p>Bipack, with 3 stop exposure compensation, gives a middle grey (<code>ND1.10</code>)</p>
</blockquote> </blockquote>
<p>Example 2:</p> <p>Example 2:</p>
<blockquote> <blockquote>
<p>Image A is maximum red (<code>CC250Y</code>+<code>CC250M</code>) Image B is maximum green (<code>CC250Y</code>+<code>CC250C</code>)</p> <p>Image A is maximum red (<code>CC250Y</code>+<code>CC250M</code>)</p>
<p>Image B is maximum green (<code>CC250Y</code>+<code>CC250C</code>)</p>
</blockquote> </blockquote>
<blockquote> <blockquote>
<p>Double exposure from positives gives yellow (<code>CC220Y</code>+<code>ND.3</code>) Double exposure from negatives givee black (<code>CC30Y</code>+<code>ND2.20</code>) Bipack, with 3 stop exposure compensation, gives brown (<code>CC9OY</code>+<code>ND1.60</code>)</p> <p>Double exposure from positives gives yellow (<code>CC220Y</code>+<code>ND.3</code>)</p>
<p>Double exposure from negatives gives black (<code>CC30Y</code>+<code>ND2.20</code>)</p>
<p>Bipack, with 3 stop exposure compensation, gives brown (<code>CC9OY</code>+<code>ND1.60</code>)</p>
</blockquote> </blockquote>
<p>Example 3:</p> <p>Example 3:</p>
<blockquote> <blockquote>
<p>Image A is a flesh (<code>CC30Y</code>+<code>CC20M</code>+<code>CC10C</code>) Image B is sky (<code>CC6OM</code>+<code>CC80C</code>)</p> <p>Image A is a flesh (<code>CC30Y</code>+<code>CC20M</code>+<code>CC10C</code>)</p>
<p>Image B is sky (<code>CC6OM</code>+<code>CC80C</code>)</p>
</blockquote> </blockquote>
<blockquote> <blockquote>
<p>Double exposure from positives gives (<code>CC12Y</code>+<code>CC36M</code>+<code>CC32C</code>) Double exposure from negatives gives (<code>CC18Y</code>+<code>CC45M</code>+<code>CC58C</code>) Bipack, with 1 stop exposure compensation, gives (<code>CCSOM</code>+<code>CC60C</code>)</p> <p>Double exposure from positives gives (<code>CC12Y</code>+<code>CC36M</code>+<code>CC32C</code>)</p>
<p>Double exposure from negatives gives (<code>CC18Y</code>+<code>CC45M</code>+<code>CC58C</code>)</p>
<p>Bipack, with 1 stop exposure compensation, gives (<code>CC50M</code>+<code>CC60C</code>)</p>
</blockquote> </blockquote>
<p><a name="weighted-double-exposures"></a></p> <p><a name="weighted-double-exposures"></a></p>
<h2 id="weighted-double-exposures">WEIGHTED DOUBLE EXPOSURES</h2> <h2 id="weighted-double-exposures">WEIGHTED DOUBLE EXPOSURES</h2>
@ -1281,9 +1294,9 @@
<p>A dissolve begins with one picture. Then a second picture gradually appears, all over the frame, shares the frame with the first picture, and gradually replaces it.</p> <p>A dissolve begins with one picture. Then a second picture gradually appears, all over the frame, shares the frame with the first picture, and gradually replaces it.</p>
<p>The traditional dissolve is a simultaneous (double exposed) linear fadeout of the first image and linear fadein of the second, made from positive images.</p> <p>The traditional dissolve is a simultaneous (double exposed) linear fadeout of the first image and linear fadein of the second, made from positive images.</p>
<p>A simultaneous log fadeout and log fadein makes quite a lumpy dissolve (becoming dark midway, from positive images).</p> <p>A simultaneous log fadeout and log fadein makes quite a lumpy dissolve (becoming dark midway, from positive images).</p>
<p>Regular dissolves are planned as if for variable shutters. At each frame the shutter angles for the two exposures must sun to the full shutter angle. ND equivalents can be found in Chart C and ND filters can be used to make the dissolve.</p> <p>Regular dissolves are planned as if for variable shutters. At each frame the shutter angles for the two exposures must sum to the full shutter angle. ND equivalents can be found in Chart C and ND filters can be used to make the dissolve.</p>
<p>It is not necessary for the fadeout and the fadein to be the same or even of the same type. Any chosen fadeout has a complementary fadein (found by subtractions from full shutter angle), and vice versa.</p> <p>It is not necessary for the fadeout and the fadein to be the same or even of the same type. Any chosen fadeout has a complementary fadein (found by subtractions from full shutter angle), and vice versa.</p>
<p>A dissolve from negative originals is made by pretending they are positives and following the method for positives. No dissolve made from negative originale will look the same as a dissolve made from the corresponding positive originals.</p> <p>A dissolve from negative originals is made by pretending they are positives and following the method for positives. No dissolve made from negative originals will look the same as a dissolve made from the corresponding positive originals.</p>
<p><a name="effects-dissolves"></a></p> <p><a name="effects-dissolves"></a></p>
<h2 id="effects-dissolves">EFFECTS DISSOLVES</h2> <h2 id="effects-dissolves">EFFECTS DISSOLVES</h2>
<p>Dissolves are great smoothers, not only between scenes but between “effects”.</p> <p>Dissolves are great smoothers, not only between scenes but between “effects”.</p>
@ -1295,19 +1308,20 @@
<p>If a dissolve is made between a negative original and a clear (or orange) film the result resembles a fadeout. For the fadeocut to resemble a log fadeout a special dissolve is required. The clear film is faded in approximately logarithmically, and the negative is faded out complementarily.</p> <p>If a dissolve is made between a negative original and a clear (or orange) film the result resembles a fadeout. For the fadeocut to resemble a log fadeout a special dissolve is required. The clear film is faded in approximately logarithmically, and the negative is faded out complementarily.</p>
<p><a name="color-exposure"></a></p> <p><a name="color-exposure"></a></p>
<h2 id="color-exposure">COLOR EXPOSURE</h2> <h2 id="color-exposure">COLOR EXPOSURE</h2>
<p>The earlier discussione of exposure apply as well to color printing except that now color and brightness are adjustable. The adjustments are made primarily with CC filters and ND filters.</p> <p>The earlier discussions of exposure apply as well to color printing except that now color and brightness are adjustable. The adjustments are made primarily with CC filters and ND filters.</p>
<p>A <code>CCY--</code> filter works roughly like an <code>ND.--</code> filter on just the blue part of the spectrum, while not affecting the rest of the spectrum. Similarly a <code>CCM</code> filter cuts the green and a <code>CCC</code> filter cute the red. ND filters could be eliminated by CC filters. For example, <code>ND.30</code> is roughly <code>CC30Y</code>+<code>CC30M</code>+<code>CC30C</code>. This elimination is seldom practical and slightly inferior spectrally.</p> <p>A <code>CCY--</code> filter works roughly like an <code>ND.--</code> filter on just the blue part of the spectrum, while not affecting the rest of the spectrum. Similarly a <code>CCM</code> filter cuts the green and a <code>CCC</code> filter cuts the red. ND filters could be eliminated by CC filters. For example, <code>ND.30</code> is roughly <code>CC30Y</code>+<code>CC30M</code>+<code>CC30C</code>. This elimination is seldom practical and slightly inferior spectrally.</p>
<p>Color adjustments are made secondarily with UV filters, IR filters, and band rejection filters.</p> <p>Color adjustments are made secondarily with UV filters, IR filters, and band rejection filters.</p>
<p>As with B&amp;W, correction of misexposed originals should be done in earlier rather than later printing steps.</p> <p>As with B&amp;W, correction of misexposed originals should be done in earlier rather than later printing steps.</p>
<p><a name="testing"></a></p> <p><a name="testing"></a></p>
<h2 id="testing">TESTING</h2> <h2 id="testing">TESTING</h2>
<p>For a general color exposure determination, the test original should be a well-exposed film of the relevant kind, preferably with large areas of near-neutral mid-tones.</p> <p>For a general color exposure determination, the test original should be a well-exposed film of the relevant kind, preferably with large areas of near-neutral mid-tones.</p>
<p>Jointly varying CC and ND filtration, a long series of test exposures is made. The developed print is compared with the original. Simple resemblance to the original is less desirable than preservation of crucial qualities of the original. The decision of “right exposure” is not easy.</p> <p>Jointly varying CC and ND filtration, a long series of test exposures is made. The developed print is compared with the original. Simple resemblance to the original is less desirable than preservation of crucial qualities of the original. The decision of “right exposure” is not easy.</p>
<p>It is tempting to shorten the test by varying CC and ND separately. An ND value is fixed and the CC’s varied. A CC value is fixed and the ND’s varied. This makes decisions the more difficult, reguiring beat-color judgements on off-brightnees pictures and best-brightness judgements on off-color pictures. This leads to simplietic criteria for decision.</p> <p>It is tempting to shorten the test by varying CC and ND separately. An ND value is fixed and the CC’s varied. A CC value is fixed and the ND’s varied. This makes decisions the more difficult, requiring best-color judgements on off-brightnees pictures and best-brightness judgements on off-color pictures. This leads to simplistic criteria for decision.</p>
<p>Example of a joint color and brightness test:</p> <p>Example of a joint color and brightness test:</p>
<blockquote> <blockquote>
<p>Each line in the chart represents CC filtration to be added to an initial guess of the right CC’s. At each line make a series of ND variations surrounding an initial guess of the right ND. Perhaps the guess -.50, -.40, -.30, -.20, -.10, the guese itself, +.10, +.20, and +.30. The series is lopsided because the CC filtrations are all added to the CC guess. The 37 CC variations X the 9 ND variations = a 333 frame test.</p> <p>Each line in the chart represents CC filtration to be added to an initial guess of the right CC’s. At each line make a series of ND variations surrounding an initial guess of the right ND. Perhaps the guess -.50, -.40, -.30, -.20, -.10, the guess itself, +.10, +.20, and +.30. The series is lopsided because the CC filtrations are all added to the CC guess.</p>
</blockquote> </blockquote>
<p>The 37 CC variations X the 9 ND variations = a 333 frame test.</p>
<div class="ymcTable"> <div class="ymcTable">
<table> <table>
<thead> <thead>
@ -1507,11 +1521,11 @@
</table> </table>
</div> </div>
<p><strong><img src="../img/image_9.svg" alt="Diagram depicting the CC chart plotted on 3 axes: +M, +Y, +C" /></strong></p> <p><strong><img src="../img/image_9.svg" alt="Diagram depicting the CC chart plotted on 3 axes: +M, +Y, +C" /></strong></p>
<p>A joint color and brightness test is a net spread over the logical region around an initial guesea, to catch the right exposure.</p> <p>A joint color and brightness test is a net spread over the logical region around an initial guess, to catch the right exposure.</p>
<p>The 37 line test in the example ia a rather fine 10-20-30 net usable when there is fair confidence in the initial guess.</p> <p>The 37 line test in the example ia a rather fine 10-20-30 net usable when there is fair confidence in the initial guess.</p>
<p>When there is better confidence in the guegse the test could be abridged to a 19 line 10-20 net (by omitting the lines with 30’s) and the ND variations also reduced.</p> <p>When there is better confidence in the guess the test could be abridged to a 19 line 10-20 net (by omitting the lines with 30’s) and the ND variations also reduced.</p>
<p>Very fine adjustments to color exposure, requiring tests with increments finer than <code>CC10</code> and <code>ND.10</code>, are only justified when two color exposures must match in two parts of one frame, or in rapidly succeeding frames. As absolute adjustments, <code>CCO5</code> and <code>CCO25</code> are too likely to be defeated by the processing lab.</p> <p>Very fine adjustments to color exposure, requiring tests with increments finer than <code>CC10</code> and <code>ND.10</code>, are only justified when two color exposures must match in two parts of one frame, or in rapidly succeeding frames. As absolute adjustments, <code>CCO5</code> and <code>CCO25</code> are too likely to be defeated by the processing lab.</p>
<p>When there is little confidence in the guess the 10-20-30 net could be modified te a sparser 20-40-60 net (by doubling all values, including the ND variations). This is still a 37 line test. A 10-20-30-40-50-60 net would require a painfully long chart (253 lines!). A time and money and time problem arises: whether to do the huge test and determine the right exposure now, or to do a coarse test and almost determine the right exposure and perhaps have to do a finer retest.</p> <p>When there is little confidence in the guess the 10-20-30 net could be modified to a coarser 20-40-60 net (by doubling all values, including the ND variations). This is still a 37 line test. A 10-20-30-40-50-60 net would require a painfully long chart (253 lines!). A time and money and time problem arises: whether to do the huge test and determine the right exposure now, or to do a coarse test and almost determine the right exposure and perhaps have to do a finer retest.</p>
<p>Other test series can be designed with specific goals. Also the variations can be incorporated into the guess, rather than added on, for improved accuracy.</p> <p>Other test series can be designed with specific goals. Also the variations can be incorporated into the guess, rather than added on, for improved accuracy.</p>
<p><a name="cc-pack-reduction"></a></p> <p><a name="cc-pack-reduction"></a></p>
<h2 id="cc-pack-reduction">CC PACK REDUCTION</h2> <h2 id="cc-pack-reduction">CC PACK REDUCTION</h2>
@ -1519,17 +1533,21 @@
<p>Method:</p> <p>Method:</p>
<blockquote> <blockquote>
<ol type="1"> <ol type="1">
<li>change <code>CCB</code> to <code>COM</code>+<code>CCC</code> change <code>CCG</code> to <code>CCY</code>+<code>CCC</code> change <code>CCR</code> to <code>CCY</code>+<code>CCM</code></li> <li>change <code>CCB</code> to <code>CCM</code>+<code>CCC</code></li>
</ol> </ol>
<p>change <code>CCG</code> to <code>CCY</code>+<code>CCC</code></p>
<p>change <code>CCR</code> to <code>CCY</code>+<code>CCM</code></p>
</blockquote> </blockquote>
<blockquote> <blockquote>
<ol start="2" type="1"> <ol start="2" type="1">
<li>add together all <code>CCY</code> add together all <code>CCM</code> add together all <code>CCC</code></li> <li>add together all <code>CCY</code></li>
</ol> </ol>
<p>add together all <code>CCM</code></p>
<p>add together all <code>CCC</code></p>
</blockquote> </blockquote>
<blockquote> <blockquote>
<ol start="3" type="1"> <ol start="3" type="1">
<li>whichever of the three kinds has the smallest total in step 2 is eliminated. An equal amount of ND is added. An equal amount is subtracted from the regaining two kinds in step 2.</li> <li>whichever of the three kinds has the smallest total in step 2 is eliminated. An equal amount of ND is added. An equal amount is subtracted from the remaining two kinds in step 2.</li>
</ol> </ol>
</blockquote> </blockquote>
<ol start="4" type="1"> <ol start="4" type="1">
@ -1539,8 +1557,8 @@
<ol type="1"> <ol type="1">
<li>pack becomes <code>CC20Y</code>+<code>CC1OC</code>+<code>CC40Y</code>+<code>CC40M</code></li> <li>pack becomes <code>CC20Y</code>+<code>CC1OC</code>+<code>CC40Y</code>+<code>CC40M</code></li>
<li>pack becomes <code>CC60Y</code>+<code>CC40M</code>+<code>CC10C</code></li> <li>pack becomes <code>CC60Y</code>+<code>CC40M</code>+<code>CC10C</code></li>
<li>pack becomes <code>CC5OY</code>+<code>CC3OM</code>+<code>ND.10</code></li> <li>pack becomes <code>CC50Y</code>+<code>CC30M</code>+<code>ND.10</code></li>
<li>pack becomes <code>CC5OY</code>+<code>CC3OM</code>+<code>ND.14</code></li> <li>pack becomes <code>CC50Y</code>+<code>CC30M</code>+<code>ND.14</code></li>
</ol> </ol>
<p><a name="high-contrast-prints"></a></p> <p><a name="high-contrast-prints"></a></p>
<h2 id="high-contrast-prints">HIGH CONTRAST PRINTS</h2> <h2 id="high-contrast-prints">HIGH CONTRAST PRINTS</h2>
@ -1560,25 +1578,25 @@
<p><a name="contrast-building-steps"></a></p> <p><a name="contrast-building-steps"></a></p>
<h2 id="contrast-building-steps">CONTRAST BUILDING STEPS</h2> <h2 id="contrast-building-steps">CONTRAST BUILDING STEPS</h2>
<p>A hicon print of a hicon print is an exaggeration of an exaggeration of tone differences.</p> <p>A hicon print of a hicon print is an exaggeration of an exaggeration of tone differences.</p>
<p>All but. a three stop range of tones in the first hicon print clear or black in the second hicon. But this three stop range resulted from a 3/4 stop range in the original. That is, all but a tiny part of the picture should now be either clear or black.</p> <p>All but a three stop range of tones in the first hicon print clear or black in the second hicon. But this three stop range resulted from a 3/4 stop range in the original. That is, all but a tiny part of the picture should now be either clear or black.</p>
<p>If the first hicon had gamma 4, the second hicon had effective gamma 16, the third had effective gamma 64, and so on.</p> <p>If the first hicon had gamma 4, the second hicon had effective gamma 16, the third had effective gamma 64, and so on.</p>
<p>After 3, 4, or 5 hicon generations a high contrast mask ia derived from the continuous tone original. It is, practically, all clear and black.</p> <p>After 3, 4, or 5 hicon generations a high contrast mask ia derived from the continuous tone original. It is, practically, all clear and black.</p>
<p><a name="hicon-speckle"></a></p> <p><a name="hicon-speckle"></a></p>
<h2 id="hicon-speckle">HICON SPECKLE</h2> <h2 id="hicon-speckle">HICON SPECKLE</h2>
<p>No area of middle tone survives generation after generation on 7362. Its graininess makes it not a single tone. So this tone pattern is made starker and coarser by each contrast building step, becoming a black and clear speckle.</p> <p>No area of middle tone survives generation after generation on 7362. Its graininess makes it not a single tone. So this tone pattern is made starker and coarser by each contrast building step, becoming a black and clear speckle.</p>
<p>To avoid speckle, exposure must be adjusted at an early step, before there is black and clear in the pattern, to force the whole area to clear or to black.</p> <p>To avoid speckle, exposure must be adjusted at an early step, before there is black and clear in the pattern, to force the whole area to clear or to black.</p>
<p>To promote speckle, exposure is adjuated to hold the area in the greys through several steps.</p> <p>To promote speckle, exposure is adjusted to hold the area in the greys through several steps.</p>
<p><a name="tone-isolation"></a></p> <p><a name="tone-isolation"></a></p>
<h2 id="tone-isolation">TONE ISOLATION</h2> <h2 id="tone-isolation">TONE ISOLATION</h2>
<p>The parts of an original which share a single tone can be isolated by a hicon mask derived from the original as follows (all printing steps being exact 1:1):</p> <p>The parts of an original which share a single tone can be isolated by a hicon mask derived from the original as follows (all printing steps being exact 1:1):</p>
<ol type="1"> <ol type="1">
<li>make a negative hicon from the original with exposure adjusted to make the chosen tone go light, while tones somewhat lighter than it go dark;</li> <li>make a negative hicon from the original with exposure adjusted to make the chosen tone go light, while tones somewhat lighter than it go dark;</li>
<li>bipack the original with the result of 1, printing onto hicon negative;</li> <li>bipack the original with the result of 1, printing onto hicon negative;</li>
<li>additional contrast building steps ae necessary.</li> <li>additional contrast building steps as necessary.</li>
</ol> </ol>
<p><a name="logic-of-mask-combination"></a></p> <p><a name="logic-of-mask-combination"></a></p>
<h2 id="logic-of-mask-combination">LOGIC OF MASK COMBINATION</h2> <h2 id="logic-of-mask-combination">LOGIC OF MASK COMBINATION</h2>
<p>Hicon masks being ail clear and black obey simplified rules of superposition. With appropriate exposure, printing onto hicon negative, the rules are:</p> <p>Hicon masks being all clear and black obey simplified rules of superposition. With appropriate exposure, printing onto hicon negative, the rules are:</p>
<ol type="1"> <ol type="1">
<li>In double exposure, where there is black in both originals becomes clear. The rest becomes black.</li> <li>In double exposure, where there is black in both originals becomes clear. The rest becomes black.</li>
<li>In bipack, where there is clear in both originals becomes black. The rest becomes clear.</li> <li>In bipack, where there is clear in both originals becomes black. The rest becomes clear.</li>
@ -1594,7 +1612,7 @@
<p>Exposing a hicon print from an already hicon “original” seems non-critical. Black becomes clear and clear becomes black over several stops of exposure change. However, most of these exposures are overexposures which swell and spread the areas of black image. With the first 2 or 3 stops of overexposure the spread is microscopic. Beyond this the edges of areas give out and positively bloom.</p> <p>Exposing a hicon print from an already hicon “original” seems non-critical. Black becomes clear and clear becomes black over several stops of exposure change. However, most of these exposures are overexposures which swell and spread the areas of black image. With the first 2 or 3 stops of overexposure the spread is microscopic. Beyond this the edges of areas give out and positively bloom.</p>
<p>Bloom is pretty. It is the result of both lens diffraction and film halation. It hints that lurking under every sharp exposure, many stops down, is a secondary pattern of exposure spreading over the whole frame.</p> <p>Bloom is pretty. It is the result of both lens diffraction and film halation. It hints that lurking under every sharp exposure, many stops down, is a secondary pattern of exposure spreading over the whole frame.</p>
<p>Bloom makee it impossible to separate darker tones of a continuous tone original with a hicon print by brute force of exposure adjustment.</p> <p>Bloom makee it impossible to separate darker tones of a continuous tone original with a hicon print by brute force of exposure adjustment.</p>
<p>Image spread is the result of edge unsharpness of both lena and film. It makes the high contrast photography of tiny details, like fine print, difficult.</p> <p>Image spread is the result of edge unsharpness of both lens and film. It makes the high contrast photography of tiny details, like fine print, difficult.</p>
<p>Reversal processed hicon can show image shrink as well as image spread, and at exactly the right exposure, neither.</p> <p>Reversal processed hicon can show image shrink as well as image spread, and at exactly the right exposure, neither.</p>
<p>Usually overexposing the hicon is unnecessary. Not quite black blacks indicates a safe exposure, and all that is needed if there will be a later hicon generation.</p> <p>Usually overexposing the hicon is unnecessary. Not quite black blacks indicates a safe exposure, and all that is needed if there will be a later hicon generation.</p>
<p><a name="mask-and-countermask"></a></p> <p><a name="mask-and-countermask"></a></p>
@ -1611,9 +1629,9 @@
<p><a name="reversal-negative-fitting"></a></p> <p><a name="reversal-negative-fitting"></a></p>
<h2 id="reversalnegative-fitting">REVERSAL/NEGATIVE FITTING</h2> <h2 id="reversalnegative-fitting">REVERSAL/NEGATIVE FITTING</h2>
<p>A beautiful trick allows well-fitted mask pairs without exact 1:1 setup. They are made by exposing two lengths of 7362 from the same hicon original using the identical (undisturbed) setup. One length is proceseed negative and the other is processed reversal. They are the mask and countermask. The original may be discarded.</p> <p>A beautiful trick allows well-fitted mask pairs without exact 1:1 setup. They are made by exposing two lengths of 7362 from the same hicon original using the identical (undisturbed) setup. One length is proceseed negative and the other is processed reversal. They are the mask and countermask. The original may be discarded.</p>
<p>For perfection, exposures are adjusted so the slight spreading of black in the negative print as equal to the slight spreading of clear in the reversal print.</p> <p>For perfection, exposures are adjusted so the slight spreading of black in the negative print is equal to the slight spreading of clear in the reversal print.</p>
<p>This mask and countermask might fit each other exactly, but if the setup wasn’t exact 1:1 they will not fit their common source exactly, which may or may not matter. Also the perfection of fit is with respect to the camera’s registration system. If the printer gate has a different system, then that perfection will soon be lost.</p> <p>This mask and countermask might fit each other exactly, but if the setup wasn’t exact 1:1 they will not fit their common source exactly, which may or may not matter. Also the perfection of fit is with respect to the camera’s registration system. If the printer gate has a different system, then that perfection will soon be lost.</p>
<p>This problem arose above in AIMFRAME. Simply, an optical printer with unmatched camera and gate registration mechanism, however excellent they may be, is doomed to registration defects in most affects.</p> <p>This problem arose above in AIMFRAME. Simply, an optical printer with unmatched camera and gate registration mechanism, however excellent they may be, is doomed to registration defects in most effects.</p>
<p><a name="feathered-masks"></a></p> <p><a name="feathered-masks"></a></p>
<h2 id="feathered-masks">FEATHERED MASKS</h2> <h2 id="feathered-masks">FEATHERED MASKS</h2>
<p>If mask and countermask are soft-edged instead of hard-edged then they blend inatead of flit, and thie is highly tolerant of registration defecte and inexact 1:1</p> <p>If mask and countermask are soft-edged instead of hard-edged then they blend inatead of flit, and thie is highly tolerant of registration defecte and inexact 1:1</p>
@ -1622,22 +1640,27 @@
<p><a name="image-marriage"></a></p> <p><a name="image-marriage"></a></p>
<h2 id="image-marriage">IMAGE MARRIAGE</h2> <h2 id="image-marriage">IMAGE MARRIAGE</h2>
<p>Wipes, inserts, splitscreens, colored titles, etc. are all examples of the same technique. One picture is bipacked with one mask and this is exposed onto a pictorial print film. Another picture is bipacked with the countermask and this is exposed onto the same frames of print film. The mask and countermask partition the frame for the two pictures. There is no black region and no region of pictorial double exposure in the print.</p> <p>Wipes, inserts, splitscreens, colored titles, etc. are all examples of the same technique. One picture is bipacked with one mask and this is exposed onto a pictorial print film. Another picture is bipacked with the countermask and this is exposed onto the same frames of print film. The mask and countermask partition the frame for the two pictures. There is no black region and no region of pictorial double exposure in the print.</p>
<p>Any pair of maak and countermask, where one proceeds gradually from all clear to all black (the other from all black to all clear) defines a wipe. “Proceeds gradually” is subject to interpretation.</p> <p>Any pair of mask and countermask, where one proceeds gradually from all clear to all black (the other from all black to all clear) defines a wipe. “Proceeds gradually” is subject to interpretation.</p>
<p>Pretty nearly all image marriages fall into three categories:</p> <p>Pretty nearly all image marriages fall into three categories:</p>
<p><strong><img src="../img/image_10.svg" alt="Graphic depicting three examples of travelling matte marriages, I, II, and III" /></strong></p> <p><strong><img src="../img/image_10.svg" alt="Graphic depicting three examples of travelling matte marriages, I, II, and III" /></strong></p>
<p>I. One region takes its shape from the things pictured within it. II. One region takes its shape from the things pictured around it III. One region takes its shape from some not-pictured thing.</p> <p>I. One region takes its shape from the things pictured within it.</p>
<ol start="2" type="I">
<li><p>One region takes its shape from the things pictured around it</p></li>
<li><p>One region takes its shape from some not-pictured thing.</p></li>
</ol>
<p><a name="mask-blackness"></a></p> <p><a name="mask-blackness"></a></p>
<h2 id="mask-blackness">MASK BLACKNESS</h2> <h2 id="mask-blackness">MASK BLACKNESS</h2>
<p>For successful image marriage the black of the hicon mask should be about 3 stops darker than the black of the picture which will f1l1 the black region.</p> <p>For successful image marriage the black of the hicon mask should be about 3 stops darker than the black of the picture which will fill the black region.</p>
<p><a name="hicons-from-color-originals"></a></p> <p><a name="hicons-from-color-originals"></a></p>
<h2 id="hicons-from-color-originals">HICONS FROM COLOR ORIGINALS</h2> <h2 id="hicons-from-color-originals">HICONS FROM COLOR ORIGINALS</h2>
<p>7362 film is sensitive to blue light only. For example, it cannot “see” the brightness difference between white and bright blue, or between yellow and red.</p> <p>7362 film is sensitive to blue light only. For example, it cannot “see” the brightness difference between white and bright blue, or between yellow and red.</p>
<p>Color filtering with 7362 hae either no effect, or the effect of ND filtration.</p> <p>Color filtering with 7362 has either no effect, or the effect of ND filtration.</p>
<p>If a hicon mask is wanted, based on color differences, either</p> <p>If a hicon mask is wanted, based on color differences, either</p>
<p>I. First print the original onto panchromatic continuous tone film (7276, 7235, etc.) with color filters as needed to separate the colors. Then print this onto 7362.</p> <p>I. First print the original onto panchromatic continuous tone film (7276, 7235, etc.) with color filters as needed to separate the colors. Then print this onto 7362.</p>
<p>or II. Print the original onto panchromatic hicon film (7369) with color filters as needed to separate the colors.</p> <p>or II. Print the original onto panchromatic hicon film (7369) with color filters as needed to separate the colors.</p>
<p>If two colors are different, there ia a filter which will make them record differently on panchromatic film. This is simpler when the two colors are on film than when they are in the natural world, because film colors are spectrally simpler. To decide what filter best separates two film colors think of each color as made cf <code>CCY</code>, <code>CCM</code>, and <code>CCC</code>. Wherever the difference between the two colors is greatest (in the Y, the M, or the C) choose the complementary filter (B, G, R, respectively) in a strong (non-CC) version.</p> <p>If two colors are different, there is a filter which will make them record differently on panchromatic film.</p>
<p>Example: Color 1 is a flesh (<code>CC30Y</code>+<code>CC2OM</code>+<code>CC10C</code>)</p> <p>This is simpler when the two colors are on film than when they are in the natural world, because film colors are spectrally simpler. To decide what filter best separates two film colors think of each color as made of <code>CCY</code>, <code>CCM</code>, and <code>CCC</code>. Wherever the difference between the two colors is greatest (in the Y, the M, or the C) choose the complementary filter (B, G, R, respectively) in a strong (non-CC) version.</p>
<p>Example: Color 1 is a flesh (<code>CC30Y</code>+<code>CC20M</code>+<code>CC10C</code>)</p>
<p>Color 2 is sky (<code>CC0Y</code>+<code>CC60M</code>+<code>CC80C</code>)</p> <p>Color 2 is sky (<code>CC0Y</code>+<code>CC60M</code>+<code>CC80C</code>)</p>
<p>The greatest difference is in the cyan (C), so a red filter such as Wratten #29 is used to separate this flesh and sky.</p> <p>The greatest difference is in the cyan (C), so a red filter such as Wratten #29 is used to separate this flesh and sky.</p>
<p><a name="hicon-processing"></a></p> <p><a name="hicon-processing"></a></p>
@ -1647,7 +1670,7 @@
<li>Develop 6 minutes in D-11 <span class="citation" data-cites="70">@70</span>° with continuous agitation.</li> <li>Develop 6 minutes in D-11 <span class="citation" data-cites="70">@70</span>° with continuous agitation.</li>
<li>Rinse 30 seconds in stopbath or water.</li> <li>Rinse 30 seconds in stopbath or water.</li>
<li>Fix 1 1/2 minutes.</li> <li>Fix 1 1/2 minutes.</li>
<li>(7369 only. Rinse 1 minute in as Clearing Agent.)</li> <li>(7369 only. Rinse 1 minute in Hypo Clearing Agent.)</li>
<li>Wash 2 minutes in running water (longer for permanence).</li> <li>Wash 2 minutes in running water (longer for permanence).</li>
<li>Dry.</li> <li>Dry.</li>
</ol> </ol>
@ -1659,7 +1682,7 @@
<li>Clear 1 minute in CB-1 (solution of 90g Sodium Sulfite per liter of water).</li> <li>Clear 1 minute in CB-1 (solution of 90g Sodium Sulfite per liter of water).</li>
<li>Rinse 2 minutes in water. During this time flash to light: 10 seconds at 1 foot from 100 watt lamp, or equivalent exposure. This is extremely approximate. The roomlight may be left on now.</li> <li>Rinse 2 minutes in water. During this time flash to light: 10 seconds at 1 foot from 100 watt lamp, or equivalent exposure. This is extremely approximate. The roomlight may be left on now.</li>
<li>Develop 3 minutes in D-11.</li> <li>Develop 3 minutes in D-11.</li>
<li>Rinse 30 seconds in etopbath or water.</li> <li>Rinse 30 seconds in stopbath or water.</li>
<li>Fix 1 1/2 minutes.</li> <li>Fix 1 1/2 minutes.</li>
<li>Wash 2 minutes in running water (longer for permanence).</li> <li>Wash 2 minutes in running water (longer for permanence).</li>
<li>Dry.</li> <li>Dry.</li>

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