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NOTES_ON_OPTICAL_PRINTER_TECHNIQUE.md
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@ -1047,3 +1047,486 @@ But for colors, not only are new colors produced but apparent brightnesses do no
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.
Example 1:
> Image & is orange (`CC200Y`+`CC100M`)
> Image B ts blue (`CC100M`+`CC200C`)
> 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`)
> Bipack, with 3 stop exposure compensation, gives a middle grey (`ND1.10`)
Example 2:
> Image A is maximum red (`CC250Y`+`CC250M`)
> Image B is maximum green (`CC250Y`+`CC250C`)
> Double exposure from positives gives yellow (`CC220Y`+`ND.3`)
> Double exposure from negatives givee black (`CC30Y`+`ND2.20`)
> Bipack, with 3 stop exposure compensation, gives brown (`CC9OY`+`ND1.60`)
Example 3:
> Image A is a flesh (`CC30Y`+`CC20M`+`CC10C`)
> Image B is sky (`CC6OM`+`CC80C`)
> Double exposure from positives gives (`CC12Y`+`CC36M`+`CC32C`)
> Double exposure from negatives gives (`CC18Y`+`CC45M`+`CC58C`)
> Bipack, with 1 stop exposure compensation, gives (`CCSOM`+`CC60C`)
<a name="weighted-double-exposures"></a>
## WEIGHTED DOUBLE EXPOSURES
In double and other multiple exposures there is no need to have the several exposures equal.
To plan weighted multi-exposures, work in shutter angles allotted to each original.
Typically the total will be full shutter.
Shutter angles can be converted to ND's using Chart C.
<a name="dissolves"></a>
## DISSOLVES
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.
The traditional dissolve is a simultaneous (double exposed)linear fadeout of the first image and linear fadein of the second, made 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.
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.
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.
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.
<a name="effects-dissolves"></a>
## EFFECTS DISSOLVES
Dissolves are great smoothers, not only between scenes but between "effects".
For example, a dissolve between a picture illuminated through one color filter and the same (synchronized) picture illuminated through another color filter makes a slur of colorations--a straight line course through color space--between the two.
A dissolve between a picture positive and the same (synchronized) picture negative forms a pictorial bridge from positive to negative.
The bridge is of strange stuff.
The all-grey picture is not on the way.
The mentioned strange stuff is reminiscent of Sabattier
solarization again.
The double exposure of a picture with its negative, preferably onto contrasty film, gives a reversing tonality.
Dark things become lighter than middle tone things, which remain darker than light things.
<a name="fades-from-negative"></a>
## FADES FROM NEGATIVE
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.
<a name="color-exposure"></a>
## COLOR EXPOSURE
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.
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.
Similarly a `CCM` filter cuts the green and a `CCC` filter cute the red.
ND filters could be eliminated by CC filters.
For example, `ND.30` is roughly `CC30Y`+`CC30M`+`CC30C`.
This elimination is seldom practical and slightly inferior spectrally.
Color adjustments are made secondarily with UV filters, IR filters, and band rejection filters.
As with B&W, correction of misexposed originals should be done in earlier rather than later printing steps.
<a name="testing"></a>
## TESTING
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.
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.
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.
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
test.
| Y | M | C |
|-----|-----|-----|
| 0 | 0 | 0 |
| 0 | 0 | 10 |
| 0 | 0 | 20 |
| 0 | 0 | 30 |
| 0 | 10 | 0 |
| 0 | 10 | 10 |
| 0 | 10 | 20 |
| 0 | 10 | 30 |
| 0 | 20 | 0 |
| 0 | 20 | 10 |
| 0 | 20 | 20 |
| 0 | 20 | 30 |
| 0 | 30 | 0 |
| 0 | 30 | 10 |
| 0 | 30 | 20 |
| 0 | 30 | 30 |
| 10 | 0 | 0 |
| 10 | 0 | 10 |
| 10 | 0 | 20 |
| 10 | 0 | 30 |
| 10 | 10 | 0 |
| 10 | 20 | 0 |
| 10 | 30 | 0 |
| 20 | 0 | 0 |
| 20 | 0 | 10 |
| 20 | 0 | 20 |
| 20 | 0 | 30 |
| 20 | 10 | 0 |
| 20 | 20 | 0 |
| 20 | 30 | 0 |
| 30 | 0 | 0 |
| 30 | 0 | 10 |
| 30 | 0 | 20 |
| 30 | 0 | 30 |
| 30 | 10 | 0 |
| 30 | 20 | 0 |
| 30 | 30 | 0 |
**![Diagram depicting the CC chart plotted on 3 axes: +M, +Y, +C](#)**
A joint color and brightness test is a net spread over the logical region around an initial guesea, 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.
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.
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.
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.
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.
<a name="cc-pack-reduction"></a>
## CC PACK REDUCTION
Any combination of `CCY`, `CGM`, `CCC`, and also `CCB`, `CCG`, `CCR` can be reduced to a nearly equivalent combination of just two of the first 3 kinds and some ND.
Method:
> 1. change `CCB` to `COM`+`CCC`
> change `CCG` to `CCY`+`CCC`
> change `CCR` to `CCY`+`CCM`
> 2. add together all `CCY`
> add together all `CCM`
> 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.
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,
Example: Reduce the pack `CC20Y`+`CC1OC`+`CC40R`
1. pack becomes `CC20Y`+`CC1OC`+`CC40Y`+`CC40M`
2. pack becomes `CC60Y`+`CC40M`+`CC10C`
3. pack becomes `CC5OY`+`CC3OM`+`ND.10`
4. pack becomes `CC5OY`+`CC3OM`+`ND.14`
<a name="high-contrast-prints"></a>
## HIGH CONTRAST PRINTS
The techniques for printing onto high contrast (masking) stocks are little different from those for printing onto low contrast (pictorial) stocks.
The high contrast stock itself is the tone-difference-exaggerator.
One grey tone in the original may print unchanged in the high contrast negative (hicon).
Tones a little darker than that one in the original become much lighter in the hicon.
Tones much darker than the one in the original become clear in the hicon.
Tones a little lighter than the one in the original become much darker in the hicon.
Tones much lighter than the one in the original become black in the hicon.
<a name="hicon-exposure"></a>
## HICON EXPOSURE
This makes exposing a hicon print from a continuous tone original fairly critical.
7362 stock can be developed to about gamma 4.
Then with 1 1/2 stops extra exposure, regions of the original which previously printed clear onto 7362 could print dark grey, and regions which previously printed dark grey onto 7362 will now print black.
All but about a three stop range of tones in the original print clear or black in the 7362 hicon.
Adjusting the exposure adjusts where this blunt “cut” occurs in the original.
Exposure is somewhat dependent on processing time, temperature, and agitation.
It is strongly dependent on UV filtration.
An exposure test is made by printing the original onto the hicon stock at a long series of closely spaced
exposures.
The original and print-wedge are kept for reference.
<a name="contrast-building-steps"></a>
## CONTRAST BUILDING STEPS
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.
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.
If the first hicon had gamma 4, the second hicon had effective gamma 16, the third had effective gamma 64, and so on.
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.
<a name="hicon-speckle"></a>
## HICON SPECKLE
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.
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.
<a name="tone-isolation"></a>
## TONE ISOLATION
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):
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;
3. additional contrast building steps ae necessary.
<a name="logic-of-mask-combination"></a>
## LOGIC OF MASK COMBINATION
Hicon masks being ail clear and black obey simplified rules of superposition.
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.
2. In bipack, where there is clear in both originals becomes black. The rest becomes clear.
For masks, double exposure and bipack are intimately related by these two Boolean Rules, which refer to the whole of the mask (all printing steps being exact 1:1):
1. The negative of the negative of A is the same as A.
2. The raw (unprinted) bipack of the negative of A with the negative of B is the same as the negative double exposure of A and B.
These two rules enable bipacks to be eliminated for double exposures, and vice versa.
Large multi-packs, which are impractical, are eliminated for large multi-exposures, which are practical.
<a name="image-spread-and-bloom"></a>
## IMAGE SPREAD AND BLOOM
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.
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.
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.
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.
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.
<a name="mask-and-countermask"></a>
## MASK AND COUNTERMASK
A high contrast negative print made at exact 1:1 from a high contrast mask is its "countermask".
Exact 1:1 reproduction (discussed above in AIMFRAME) is the first requirement for good fitting of the pair.
Having achieved exact 1:1 reproduction, perfectionists will notice that image spread causes a slight misfit of mask and countermask, the black regions slightly overlapping.
Three ways around this are:
1. to use the sharpest lens and film (viz. 7369), or better yet, to contact print with this film;
2. to make the countermask with spread as usual while also remaking the mask, by printing it first with excessive (double) spread and then printing that with usual spread;
3. to use reversal processed hicon as discussed below.
Changing the magnification cannot correct spreading.
<a name="reversal-negative-fitting"></a>
## REVERSAL/NEGATIVE FITTING
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.
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.
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.
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.
<a name="feathered-masks"></a>
## FEATHERED MASKS
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
Making a pair with suitable softnesses is not easy, however.
One cannot be a hicon print of the other.
Even a gamma 1 negative of a soft-edged mask will not have blendable softness.
A method involves making gamma 1 positives from a hard-edged mask pair, printed out of focus.
If gamma 1 reversal (7361) does not have sufficient black, negative-positive (7234-7366) does.
Instead of actually making soft-edged masks, the hard-edged masks, defocused, can function as soft-edged.
Since the usual use of mask pairs is in bipacks with pictures (which shouldn't be defocused) this maneuver requires either a printer camera which takes a bipack or an "aerial image" type multi-head optical printer.
In each of these the "bipacked" films are separated.
<a name="image-marriage"></a>
## IMAGE MARRIAGE
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.
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.
Pretty nearly all image marriages fall into three categories:
**![Graphic depicting three examples of travelling matte marriages, I, II, and III](#)**
I. One region takee ita shape from the things pictured within it.
II. One region takes ite shape from the things pictured around it
III. One region takes its shape from some not-pictured thing.
<a name="mask-blackness"></a>
## 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.
<a name="hicons-from-color-originals"></a>
## HICONS FROM COLOR ORIGINALS
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.
Color filtering with 7362 hae either no effect, or the effect of ND filtration.
If a hicon mask is wanted, based on color differences, either
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.
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.
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`.
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`)
Color 2 is sky (`CC0Y`+`CC60M`+`CC80C`)
The greatest difference is in the cyan (C), so a red filter such as Wratten #29 is used to separate this flesh and sky.
<a name="hicon-processing"></a>
## HICON PROCESSING
_Negative_
1. Develop 6 minutes in D-11 @70° with continuous agitation.
2. Rinse 30 seconds in stopbath or water.
3. Fix 1 1/2 minutes.
4. (7369 only. Rinse 1 minute in as Clearing Agent.)
5. Wash 2 minutes in running water (longer for permanence).
6. Dry.
_Reversal_
1. Develop 6 minutes in modified D-11 (adding 2g Sodium Thiocyanate per liter) @70° with continuous agitation.
2. Rinse 1 minute in water only.
3. Bleach 1 minute in R-9 or "Kodak Bleach".
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.
6. Develop 3 minutes in D-11.
7. Rinse 30 seconds in etopbath or water.
8. Fix 1 1/2 minutes.
9. Wash 2 minutes in running water (longer for permanence).
10. Dry.
At reversal step 5 the film looks like carved ivory.
<a name="optical-printed-release-prints"></a>
## OPTICAL PRINTED RELEASE PRINTS
The work of film art might not tolerate the extra generation to a master suitable for laboratory release printing.
Or it might require such unusual release print material or treatment of the release print material that a laboratory won't
touch it.
Then optical printed release prints are reasonable.
Sound may have to be magnetic, on a stripe applied to the finished print (preferably in emulsion position `IIIa`).
<a name="ritual-and-art"></a>
## RITUAL AND ART
Two mediums may allow production of exactly the same range of objects, but by different means.
Then different objects will in fact be made in the two mediums and the occasional identical objects will have different meanings.
Know what medium you are in.

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@ -751,3 +751,356 @@ When bipacking color negatives the extra orange mask should be neutralized by fi
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>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>
<blockquote>
<p>Image &amp; is orange (<code>CC200Y</code>+<code>CC100M</code>)
Image B ts blue (<code>CC100M</code>+<code>CC200C</code>)</p>
<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>
</blockquote>
<p>Example 2: </p>
<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>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>
</blockquote>
<p>Example 3:</p>
<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>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>
</blockquote>
<p><a name="weighted-double-exposures"></a></p>
<h2 id="weighteddoubleexposures">WEIGHTED DOUBLE EXPOSURES</h2>
<p>In double and other multiple exposures there is no need to have the several exposures equal.
To plan weighted multi-exposures, work in shutter angles allotted to each original.
Typically the total will be full shutter.
Shutter angles can be converted to ND's using Chart C.</p>
<p><a name="dissolves"></a></p>
<h2 id="dissolves">DISSOLVES</h2>
<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>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>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 name="effects-dissolves"></a></p>
<h2 id="effectsdissolves">EFFECTS DISSOLVES</h2>
<p>Dissolves are great smoothers, not only between scenes but between "effects".</p>
<p>For example, a dissolve between a picture illuminated through one color filter and the same (synchronized) picture illuminated through another color filter makes a slur of colorations--a straight line course through color space--between the two.</p>
<p>A dissolve between a picture positive and the same (synchronized) picture negative forms a pictorial bridge from positive to negative.
The bridge is of strange stuff.
The all-grey picture is not on the way.</p>
<p>The mentioned strange stuff is reminiscent of Sabattier
solarization again.
The double exposure of a picture with its negative, preferably onto contrasty film, gives a reversing tonality.
Dark things become lighter than middle tone things, which remain darker than light things.</p>
<p><a name="fades-from-negative"></a></p>
<h2 id="fadesfromnegative">FADES FROM NEGATIVE</h2>
<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>
<h2 id="colorexposure">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>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>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><a name="testing"></a></p>
<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>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>Example of a joint color and brightness test:</p>
<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>
</blockquote>
<p>| Y | M | C |
|-----|-----|-----|
| 0 | 0 | 0 |
| 0 | 0 | 10 |
| 0 | 0 | 20 |
| 0 | 0 | 30 |
| 0 | 10 | 0 |
| 0 | 10 | 10 |
| 0 | 10 | 20 |
| 0 | 10 | 30 |
| 0 | 20 | 0 |
| 0 | 20 | 10 |
| 0 | 20 | 20 |
| 0 | 20 | 30 |
| 0 | 30 | 0 |
| 0 | 30 | 10 |
| 0 | 30 | 20 |
| 0 | 30 | 30 |
| 10 | 0 | 0 |
| 10 | 0 | 10 |
| 10 | 0 | 20 |
| 10 | 0 | 30 |
| 10 | 10 | 0 |
| 10 | 20 | 0 |
| 10 | 30 | 0 |
| 20 | 0 | 0 |
| 20 | 0 | 10 |
| 20 | 0 | 20 |
| 20 | 0 | 30 |
| 20 | 10 | 0 |
| 20 | 20 | 0 |
| 20 | 30 | 0 |
| 30 | 0 | 0 |
| 30 | 0 | 10 |
| 30 | 0 | 20 |
| 30 | 0 | 30 |
| 30 | 10 | 0 |
| 30 | 20 | 0 |
| 30 | 30 | 0 |</p>
<p><strong><img src="#" 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>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>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>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>
<h2 id="ccpackreduction">CC PACK REDUCTION</h2>
<p>Any combination of <code>CCY</code>, <code>CGM</code>, <code>CCC</code>, and also <code>CCB</code>, <code>CCG</code>, <code>CCR</code> can be reduced to a nearly equivalent combination of just two of the first 3 kinds and some ND.</p>
<p>Method: </p>
<blockquote>
<ol>
<li><p>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></p></li>
<li><p>add together all <code>CCY</code>
add together all <code>CCM</code>
add together all <code>CCC</code></p></li>
<li><p>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.</p></li>
</ol>
</blockquote>
<ol start="4">
<li>count the number of CC filters in the initial and final packs. If the number has increased subtract <code>ND.O4</code> times the increase. If the number has decreased add <code>ND.O4</code> times the
decrease,</li>
</ol>
<p>Example: Reduce the pack <code>CC20Y</code>+<code>CC1OC</code>+<code>CC40R</code></p>
<ol>
<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>CC5OY</code>+<code>CC3OM</code>+<code>ND.10</code></li>
<li>pack becomes <code>CC5OY</code>+<code>CC3OM</code>+<code>ND.14</code></li>
</ol>
<p><a name="high-contrast-prints"></a></p>
<h2 id="highcontrastprints">HIGH CONTRAST PRINTS</h2>
<p>The techniques for printing onto high contrast (masking) stocks are little different from those for printing onto low contrast (pictorial) stocks.</p>
<p>The high contrast stock itself is the tone-difference-exaggerator.</p>
<p>One grey tone in the original may print unchanged in the high contrast negative (hicon).</p>
<p>Tones a little darker than that one in the original become much lighter in the hicon.</p>
<p>Tones much darker than the one in the original become clear in the hicon.</p>
<p>Tones a little lighter than the one in the original become much darker in the hicon.</p>
<p>Tones much lighter than the one in the original become black in the hicon.</p>
<p><a name="hicon-exposure"></a></p>
<h2 id="hiconexposure">HICON EXPOSURE</h2>
<p>This makes exposing a hicon print from a continuous tone original fairly critical.
7362 stock can be developed to about gamma 4.
Then with 1 1/2 stops extra exposure, regions of the original which previously printed clear onto 7362 could print dark grey, and regions which previously printed dark grey onto 7362 will now print black.</p>
<p>All but about a three stop range of tones in the original print clear or black in the 7362 hicon.
Adjusting the exposure adjusts where this blunt “cut” occurs in the original.</p>
<p>Exposure is somewhat dependent on processing time, temperature, and agitation.
It is strongly dependent on UV filtration.</p>
<p>An exposure test is made by printing the original onto the hicon stock at a long series of closely spaced
exposures.
The original and print-wedge are kept for reference.</p>
<p><a name="contrast-building-steps"></a></p>
<h2 id="contrastbuildingsteps">CONTRAST BUILDING STEPS</h2>
<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>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><a name="hicon-speckle"></a></p>
<h2 id="hiconspeckle">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>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><a name="tone-isolation"></a></p>
<h2 id="toneisolation">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>
<ol>
<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>additional contrast building steps ae necessary.</li>
</ol>
<p><a name="logic-of-mask-combination"></a></p>
<h2 id="logicofmaskcombination">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>
<ol>
<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>
</ol>
<p>For masks, double exposure and bipack are intimately related by these two Boolean Rules, which refer to the whole of the mask (all printing steps being exact 1:1):</p>
<ol>
<li>The negative of the negative of A is the same as A.</li>
<li>The raw (unprinted) bipack of the negative of A with the negative of B is the same as the negative double exposure of A and B.</li>
</ol>
<p>These two rules enable bipacks to be eliminated for double exposures, and vice versa.
Large multi-packs, which are impractical, are eliminated for large multi-exposures, which are practical.</p>
<p><a name="image-spread-and-bloom"></a></p>
<h2 id="imagespreadandbloom">IMAGE SPREAD AND BLOOM</h2>
<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 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>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><a name="mask-and-countermask"></a></p>
<h2 id="maskandcountermask">MASK AND COUNTERMASK</h2>
<p>A high contrast negative print made at exact 1:1 from a high contrast mask is its "countermask".</p>
<p>Exact 1:1 reproduction (discussed above in AIMFRAME) is the first requirement for good fitting of the pair.</p>
<p>Having achieved exact 1:1 reproduction, perfectionists will notice that image spread causes a slight misfit of mask and countermask, the black regions slightly overlapping.
Three ways around this are:</p>
<ol>
<li>to use the sharpest lens and film (viz. 7369), or better yet, to contact print with this film;</li>
<li>to make the countermask with spread as usual while also remaking the mask, by printing it first with excessive (double) spread and then printing that with usual spread;</li>
<li>to use reversal processed hicon as discussed below.</li>
</ol>
<p>Changing the magnification cannot correct spreading.</p>
<p><a name="reversal-negative-fitting"></a></p>
<h2 id="reversalnegativefitting">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>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>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><a name="feathered-masks"></a></p>
<h2 id="featheredmasks">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>Making a pair with suitable softnesses is not easy, however.
One cannot be a hicon print of the other.
Even a gamma 1 negative of a soft-edged mask will not have blendable softness.
A method involves making gamma 1 positives from a hard-edged mask pair, printed out of focus.
If gamma 1 reversal (7361) does not have sufficient black, negative-positive (7234-7366) does.</p>
<p>Instead of actually making soft-edged masks, the hard-edged masks, defocused, can function as soft-edged.
Since the usual use of mask pairs is in bipacks with pictures (which shouldn't be defocused) this maneuver requires either a printer camera which takes a bipack or an "aerial image" type multi-head optical printer.
In each of these the "bipacked" films are separated.</p>
<p><a name="image-marriage"></a></p>
<h2 id="imagemarriage">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>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>Pretty nearly all image marriages fall into three categories:</p>
<p><strong><img src="#" alt="Graphic depicting three examples of travelling matte marriages, I, II, and III" /></strong></p>
<p>I. One region takee ita shape from the things pictured within it.
II. One region takes ite shape from the things pictured around it
III. One region takes its shape from some not-pictured thing.</p>
<p><a name="mask-blackness"></a></p>
<h2 id="maskblackness">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><a name="hicons-from-color-originals"></a></p>
<h2 id="hiconsfromcolororiginals">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>Color filtering with 7362 hae either no effect, or the effect of ND filtration.</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>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>Example: Color 1 is a flesh (<code>CC30Y</code>+<code>CC2OM</code>+<code>CC10C</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><a name="hicon-processing"></a></p>
<h2 id="hiconprocessing">HICON PROCESSING</h2>
<p><em>Negative</em></p>
<ol>
<li>Develop 6 minutes in D-11 @70° with continuous agitation.</li>
<li>Rinse 30 seconds in stopbath or water.</li>
<li>Fix 1 1/2 minutes.</li>
<li>(7369 only. Rinse 1 minute in as Clearing Agent.)</li>
<li>Wash 2 minutes in running water (longer for permanence).</li>
<li>Dry.</li>
</ol>
<p><em>Reversal</em></p>
<ol>
<li>Develop 6 minutes in modified D-11 (adding 2g Sodium Thiocyanate per liter) @70° with continuous agitation.</li>
<li>Rinse 1 minute in water only.</li>
<li>Bleach 1 minute in R-9 or "Kodak Bleach".</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>Develop 3 minutes in D-11.</li>
<li>Rinse 30 seconds in etopbath or water.</li>
<li>Fix 1 1/2 minutes.</li>
<li>Wash 2 minutes in running water (longer for permanence).</li>
<li>Dry.</li>
</ol>
<p>At reversal step 5 the film looks like carved ivory.</p>
<p><a name="optical-printed-release-prints"></a></p>
<h2 id="opticalprintedreleaseprints">OPTICAL PRINTED RELEASE PRINTS</h2>
<p>The work of film art might not tolerate the extra generation to a master suitable for laboratory release printing.
Or it might require such unusual release print material or treatment of the release print material that a laboratory won't
touch it.
Then optical printed release prints are reasonable.
Sound may have to be magnetic, on a stripe applied to the finished print (preferably in emulsion position <code>IIIa</code>).</p>
<p><a name="ritual-and-art"></a></p>
<h2 id="ritualandart">RITUAL AND ART</h2>
<p>Two mediums may allow production of exactly the same range of objects, but by different means.
Then different objects will in fact be made in the two mediums and the occasional identical objects will have different meanings.
Know what medium you are in.</p>

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