1691 lines
62 KiB
Plaintext
Executable File
1691 lines
62 KiB
Plaintext
Executable File
= NOTES ON OPTICAL PRINTER TECHNIQUE
|
||
|
||
Magnification 1 Fadea in Original 14
|
||
Blowup.& Reduotion 2 Chart C: Neutral Déneity and
|
||
|
||
Blowup Sharpness 2 Equivalent Shutter
|
||
|
||
Printer Lenses 3 Angle 15
|
||
Optical Zoom 3 Image Superposition 16
|
||
Lene Aperture 3 Gamma # Bipack 16
|
||
Focusing 4 Incidentally 16
|
||
Focusing Aperture 4 Exposure Compensation 18
|
||
Focusing Precision 4 Special Originals 18
|
||
Focusing Target 4 Texturing 18
|
||
Depth of Field 4 Multi-Exposure 19
|
||
Bolex Priam 4 Multi-Pack 19
|
||
Bolex Groundglass 4 Natural Superposition 19
|
||
Defecus 4 Flashing 19
|
||
X-Y Adjustment 4 Contrast Adjustment 19
|
||
Exact 13:1 5 Color Image Superposition 20
|
||
Ainframe 5 Weighted Double Exposures 20
|
||
Franelines 6 Dissolves 21
|
||
Emulsion Position T Effects Dissolves 2}
|
||
Time 8 Fades from Negative 21
|
||
Fancy Freeze 8 Color Exposure 22
|
||
Fancy Slow 8 Testing 22
|
||
Diffusers 8 CC Pack Reduction 25
|
||
UV Filter 9 High Contrast Printa 25
|
||
IR Filter 9 Hicon Exposure 26
|
||
Green Filter 3 Contrast Building Steps 26
|
||
Filter Location 9 Hicon Speckle 26
|
||
Exposure 9 Tone Isolation 27
|
||
Exposure Adjusters 9 Logie of Mask Combination 27
|
||
Specifying Exposure 11 Image Spread and Bloom 27
|
||
Film Speed 11 Mask and Countermask 28
|
||
Right Exposure 1 Reversal/Negative Fitting 28
|
||
Generations 2 Feathered Maska 29
|
||
Bellows Formula 13 Image Marriage 2g
|
||
Fades 13 Mask Blacknesé 30
|
||
Log Fade 14 Hicona from Color Originals 30
|
||
Bolex Variable Shutter 14 Hicon Processing 30
|
||
Linear Fade 14 Optical Printed Release Prints 31
|
||
Other Fades 14 Ritual and Art 31
|
||
|
||
i on
|
||
| revisec .
|
||
NOTES ON OPTICAL PRINTER TECHNIQUE
|
||
DENNIS COUZIN
|
||
March 1983
|
||
|
||
An optical printer 18 a device for photographing the frames
|
||
of one film sco as to make another filn.
|
||
|
||
e 2 - . ,
|
||
I
|
||
Cc
|
||
|
||
It consists essentially of @ 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).
|
||
|
||
The camera and gate each have motorized intermittant filin
|
||
movements so that any frame of the "original" film can be
|
||
conveniently photographed onto any frame of the "print" filo.
|
||
|
||
The camera can be an ordinary cine camera, less its lens,
|
||
and the gate can be an ordinary cine projector, less its lens.
|
||
Ideally they have identical syatemsa of film registration, aa if
|
||
one Were the lens’ image of the other. The lens can be any
|
||
bellows mountable lens. Ideally it ie specially corrected for
|
||
the amall and nearly equal sizes of this object and image.
|
||
|
||
The camera and the lens can elide independently to and fro
|
||
the film gate. Thie adjustea the magnification and the focus of
|
||
the photography.
|
||
|
||
MAGNIFICATION If the lens is (nominally) midway between the films
|
||
|
||
when one is focused on the other, then the magnification
|
||
is 1. At M=1 (also called 1:1} the whole of the original
|
||
frame 1s photographed at a size which fllis the whole
|
||
of the print frame.
|
||
|
||
i ) oY ?
|
||
If the lens 18 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
|
||
Copyright (1983 by Dennie Couzin
|
||
|
||
r
|
||
2
|
||
magnification is greater than 1. At M>1 a part of the
|
||
original frame is photographed at a size which fille the
|
||
whole of the print frame.
|
||
If, starting from the 1:1! setup, the lene 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 M<1! the whole of the original frame is
|
||
photographed at a size wohich does not fill the whole
|
||
of the print frame. The remainder of the print frane
|
||
46 filled with a photograph of the gate as it surrounds
|
||
the original frame (ideslly perfectly black).
|
||
6 y
|
||
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 13:1 position)
|
||
there are two correct positions for the lens. One
|
||
gives M>1, the other M<}.
|
||
BLOWUP & REDUCTION The printer gate may hold Smm film and the printer
|
||
camera 16mm, or vice versa. With ap M=2 setup an
|
||
Sum original frame 18 photographed onto a whole
|
||
1énm frame. With an M=¢t setup a whole !6um original
|
||
frame is photographed onto an Smm frame. Conversion
|
||
between any two film gauges 4s possible thia way,
|
||
provided the frames have the sane proportions, as
|
||
Sum, super San, 16mm, and some 55ma do.
|
||
BLOWUP SHARPNESS A 16mm picture of a flea can be just as sharp ae
|
||
@ 16mm picture of an elephant. Fut & \é6an picture
|
||
of an Smm picture cannot be expected to be as sharp
|
||
as a t6mn picture of a 16mm picture. Pictures differ
|
||
. from thinge in having very limited detail. The 16as
|
||
blawup, even if it preserven all the pictorial detail
|
||
of the mm original, spreads it out, so the blowup
|
||
ie less sharp absolutely than the original.
|
||
|
||
,
|
||
3
|
||
|
||
Under extreme magnification -- a microscope objec
|
||
eould be the printer lene -- pictorial detail i: diffuse
|
||
and the underlying natural thing, the enulsion, is all
|
||
that could be photographed sharply. But the grains are
|
||
too small to be sharply imaged with light. Here even
|
||
the natural thing haa been photographically exhausted,
|
||
an 8mm original blown up to 16mm and projected will
|
||
appear sharper than the sane 8mm original optically
|
||
printed onto Smm and projected. If the blowup optics
|
||
are good thie is even true when the 1:1 printing is by
|
||
contact. Likewise for 16mm to 35mm. (This ie all due
|
||
to the print film being in effect twice as sharp and
|
||
half as grainy in a bigger frame.)
|
||
|
||
PRINTER LENSES A lens well-corrected for M-1 is less well-corrected
|
||
|
||
for M=? (or M=t). A lene Wwell-corrected for M=2 is
|
||
leas wall-corrected for M=4 (or M=%). Etc. (Floating
|
||
elementea improve this.) A lens well-corrected for M=1
|
||
for a larger format is lees than ideal for M-1 for a
|
||
smaller format. With such specialization (and expense)
|
||
in optical printer optics what ie the hope for the
|
||
|
||
$50 SOmm enlarger lens, optimized for M=.1 and much too
|
||
large a format? Wot bac, provided the sharpest aperture
|
||
ie found and heeded and focusing technique is eine.
|
||
Aleo, for Mé! ano asyunetrical lens should be mounted
|
||
the right way, which is usually with its smaller glass
|
||
facing the smaller image.
|
||
|
||
A very sharp cheap printer lens is the Canon Macrophoto
|
||
35mm £/2.8.
|
||
|
||
OPTICAL ZOOM Optical printers do not use soom lenses, although they could.
|
||
An optical printer toom is made by moving the camera and
|
||
lene each frame, so as to vary magnification while holding
|
||
focus. It is a dolly shot! A dolly abot is equivalent
|
||
to a toom for a flat subject.
|
||
|
||
Geometrically this zoom oan be identical to a zoom had
|
||
|
||
it been made in the original photography. It can also
|
||
|
||
be deviant, by tracking not to the center of the frame.
|
||
Pictorially the zoom gets grainy, showing that it was
|
||
|
||
not made in the original photography.
|
||
|
||
Rather than focua at each frame, camera am lene positions
|
||
can be precharted for, say, every 10th frame, and the other
|
||
positions interpolated or computed. On the J-E, counting
|
||
the turns of the lead screw ie a means of repeatable
|
||
positioning. A follo¥-focus sechanian is @ boon to optical
|
||
Z£oons.
|
||
|
||
The rate and course of s00ming is a factor of style,
|
||
|
||
as it is in original cinematography.
|
||
|
||
LESS APERTURE” For picture taking the printer lens should be at whichever
|
||
aperture gives the sharpest pictures. This 4e found in
|
||
teste. If a lens must be atopped down past f/8 to reach
|
||
optimum it is a terrible printer lene.
|
||
|
||
F
|
||
4
|
||
FOCUSING Printer focusing procedure is different at different magnifi
|
||
At 1:1 the camera, not the lens, 4e moved for focusing,’ Gulp)
|
||
at magnifications greater than about 1.4 18 it better to nove
|
||
the lens for focusing.
|
||
Near the t: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).
|
||
FOCUSING APERTURE With all but the best optical printer lenses either
|
||
(1) foous at the taking aperture or (2) foous at a
|
||
larger aperture and then shift focus by a pre-established
|
||
distance before taking. This "fudge-factor" is found in
|
||
film teate.
|
||
FOCUSING PRECISION Especially when focusing stopped dowm, focus many
|
||
times (perhaps 20) and set an average position.
|
||
|
||
FOCUSING TARGET Use whatever target ie found eablest to focus on.
|
||
One caution: the fudge-factor is target dependent.
|
||
Very fine resolution targete may require different
|
||
fudge factora than coarser targete do.
|
||
|
||
DEPTH OF FIELD at indicated f/5.6 there is already more than enough
|
||
depth of field for a4 bipack, at 1:1. dAleo it ig unnecessary
|
||
to refocus when adding the second film. Likewlee when
|
||
a single film ie reversed’ emulsion to base. At larger
|
||
apertures and at larger magnifications depth of field
|
||
is lese.
|
||
|
||
BOLEX PRISM It isn't a worry. There len't a distinetion between RX
|
||
|
||
lenees and non-RX lenses for most any lens which will be
|
||
used on a bellows for optical printing.
|
||
BOLEX GROUNDGLASS Only for the best optical printer lenses, which will
|
||
be used at apertures larger than f/4, does the Bolex
|
||
groundglass need to be reset from its everyday position.
|
||
DEFOCUS To throw an image out of focua without changing ite size, if
|
||
printing at i:1, move the camera 4 distance and the lens ¢ this
|
||
dietance, in the same direction.
|
||
|
||
X-Y ADJUSTMENT Besides its to and fro movement the lene haa 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...
|
||
|
||
5
|
||
At 1:1 moving the lens up a distance d raises the viewed
|
||
field by twice 4d. Likewise for down, right, and left.
|
||
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,
|
||
On simple optical printers the only lateral ad Justment
|
||
is of the lens (rather than the heavier camera or gate).
|
||
Thie is Geometrically adequate.
|
||
But the J-K adjustments are even too flimsy for a lens.
|
||
It helps, after they are set, to gently tap the lens, ac
|
||
it finds a stable position, and then to readjust if
|
||
necessary, etc., etc.
|
||
|
||
EXACT 1:1 The lateral movements of the lens, the to-fro movements of
|
||
|
||
the lens and camera, and a tilting of the camera (if necessary)
|
||
allow the optical printer to be set for exact 1:1 reproduction.
|
||
Then the printed image is the same aize and in the same position
|
||
as the original image. If the printer lacks a tilt adjustment
|
||
the oamera may be shinmed.
|
||
|
||
AIMFRAME 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 epecially drawn to contain detaila exactly’
|
||
coinciding, as seen through the camera eyepiece, with details
|
||
permanently on the groundglass. The photograph made while the
|
||
coincidence is seen is the ainfrane.
|
||
|
||
Every groundglass has some permanent detaile, even if only ite
|
||
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
|
||
pointe for a suspect one.
|
||
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 ainframe
|
||
can be a negative of the fine-patterned reticle.
|
||
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.
|
||
The aimframe has validity only for the camera in which it was
|
||
made. It does not depend on the accuracy of the camera'a
|
||
reflex viewing eystem, only the stability of the eysten.
|
||
Whenever there is doubt about the validity of the aimfrane,
|
||
such as after a camera repair or because of wear to the filn,
|
||
the old aimframe can be registered in the printer gate, aimed
|
||
on, .and photographed to make a newly valid aimframe.
|
||
|
||
For rotoscoping with primitive contrapLions, 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.
|
||
|
||
Fo
|
||
6
|
||
The 1:1 accuracy of optical printing with aimframe setups ie
|
||
limited by 1. the precision in the making and then in the use
|
||
of the aimnfraze,
|
||
2. the precision in the film registration mechanians
|
||
of camera and gate,
|
||
3. only if the two mechanieme are different, the
|
||
precision in the film dimensions (perforation
|
||
and alitting).
|
||
Btep contact printing, Buch 48 by bipacking in the optical printer
|
||
eamera, if & convenient method for making exact 1:1 reproductions.
|
||
It must give exposures which are exact 1:1, but there 18 then sone
|
||
shrinkage in processing. Optical printing with the ainfrane methoc
|
||
compensates for processing shrinkage. Shrinkage errore are too
|
||
apall to matter with simple printers.
|
||
|
||
GAMEFRAME A atrip of identical frames, shot in the optical printer camera,
|
||
is cut in two and registered in both the printer gate (upright,
|
||
eanulgion away from lene) and the camera gate (ae it was shot).
|
||
|
||
The coincidence of detaile of image and sameframe is viewed throug
|
||
an opening in the rear of a special pressure plate. <A prismatic
|
||
gate focuser may be pubstituted for the pressure plate, but only
|
||
the most positive registration systems will be unaffected by this.
|
||
Only the most solid optical printers will allow loading the carers
|
||
without diesturblog thé setup.
|
||
The sameframe method does not compensate for processing shrinkage.
|
||
FRAMELINES 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 lene should deviate from the
|
||
|
||
aimframe setup, to compensate for thia. Otherwise the print
|
||
|
||
will have a very thick, or even 4 double frameline.
|
||
|
||
Sometimes the sole reason for optical printing is to ad juat
|
||
|
||
the height of the frameline of an original fim shot with
|
||
|
||
a Wayward camera. Sometimes it is to simulate such filo.
|
||
|
||
Then the printer camera must have ite frameline adjusted.
|
||
|
||
For a Bolex thie is a simple claw exchange (revertible).
|
||
|
||
To make a frameline adjustzent, 4f 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 framelins
|
||
|
||
just appears, then until the lower frageline just appears,
|
||
|
||
and the two adjustments averaged.
|
||
|
||
If the reflex viewfinder is untrustworthy, then a camera
|
||
|
||
gate focuser can be used. Or thia method: register in ye
|
||
|
||
printer gate a bipack of the original with any file ahot in
|
||
|
||
the printer camera. Determine how much vertical adjuetaent
|
||
|
||
separates their framelines. Make that puch adjustment to
|
||
|
||
the aimfrane setup.
|
||
|
||
The framelines of the original can always be eliminated
|
||
|
||
from the print by setting the magnification slightly greater
|
||
|
||
than 1..
|
||
|
||
7
|
||
EMULSION POSITION A priori, a film of an alphabet could be any of these
|
||
eight ways.
|
||
F lh
|
||
F Sc G
|
||
¢||e FE
|
||
F F
|
||
Ia Ib IIa IIb
|
||
—__ —— ls
|
||
4 4 5 2
|
||
12) |
|
||
o 4 a
|
||
IIIa IIIb IVa IVb .
|
||
Each sketch showa emulsion facing out. For doubie
|
||
perf film there are only four ways. The a and b ways
|
||
become the sane.
|
||
Camera original is IIIa. *
|
||
A contact print from camera original is Ib.
|
||
A contact print from a contact print from canera
|
||
original is IIIa again. Etc.
|
||
All the othere are shams ~-- either optical printing
|
||
errors or elae films of alphabets somehow reversed.
|
||
Given a double perforated I, II, III, or IV it is easy
|
||
to make a double perforated optical print whioh ia
|
||
any of the four.
|
||
Single perforated filme are a pain in the side. Given,
|
||
for example, IIIa, it ia possible with a usual optical
|
||
printer to make either Ib, IIb, IIIa, or IVa, but none
|
||
of the other four. These could be made via a double
|
||
perforated intermediate. With a priem or other image
|
||
rotator, or a special reversed gate, it ie possible
|
||
to convert any of the eight ways to any of the elght ways
|
||
Figuring out how to do these is a good exercise for
|
||
the student.
|
||
The two non-sham emulsion positione are aketched again,
|
||
thie time with emulelona facing 1n shown dotted.
|
||
a O-— a o—4
|
||
- re o-— F
|
||
oS G G 6
|
||
oOo ats o—— on
|
||
CAMERA ORIGINAL CONTACT PRINT FROM
|
||
. CAMERA ORIGINAL
|
||
- Notice that when pietmres "read right" single perfs are
|
||
, on the left, and “before” .is above.
|
||
Notice that camera original reads right with emulsion
|
||
facing away. Contact print of camera original reads
|
||
right with emulsion facing toward the viewer.
|
||
|
||
8
|
||
Except when optical printing is done in alliance with
|
||
contact printing, it is usual to maintain emulsion
|
||
position through ali optical printing etepa. Atarting
|
||
with camera original each generation ie again IIIa.
|
||
For this there is a simple rule.
|
||
To reproduce the emulsion position of the original,
|
||
insert it in the printer gate with emulsion away
|
||
from lene, heads up, running upward.
|
||
Optical printing "through the base" does not degrade
|
||
image quality.
|
||
The optical printer can also imitate the contact printer,
|
||
if the original is inserted in the printer gate with
|
||
enulsion toward the lens.
|
||
TIME The optical printer gives as absolute oontrol over the flow or fits
|
||
of time as the gods could have. But it's just a movie.
|
||
|
||
Actually, two limitations on optical printer’time manipulation are
|
||
|
||
the grainy ground of film pictures and the mere 24 frames per second,
|
||
|
||
as show by these two examples.
|
||
|
||
FANCY FREEZE A single frame of the original printed repeatedly is a
|
||
freaze frame. Unfortunately the running graiu pattern
|
||
of the original freezes with the picture. The picture
|
||
has lost its ground. This can be avoided if there are
|
||
at least three frames without motion in the original, by
|
||
alternately printing among the three.
|
||
|
||
FANCY SLOW To slow motion to 3/4 speed (as is required when original
|
||
shot at 182pe is to be made into a 24fps print) it is usual
|
||
to print every third frame twice. ABCDEFGHI... becomes
|
||
ABCCDEFFGHII... . The micro-freezes, juat two frames long,
|
||
|
||
. coming every 1/6 second, are perceived through their rhythn.
|
||
This oan be avoided by randomizing the frames to be doubled
|
||
while still ohoosing one frame from each three of the original.
|
||
|
||
DIFFUSERS 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 per se, reduce sharpness;
|
||
3. reduce the apparent oontrast of B&W originals,
|
||
approximating the tonality in contact printing.
|
||
Opal glass, a more extreme diffuser than groundglaasa, is
|
||
more effective in each of the three Ways.
|
||
An opal glase oan reiuce exposure by 4 or even more stops.
|
||
An accidental or for;otten opal glass can devastate an exposure!
|
||
|
||
9
|
||
UV FILTER 4 filter which absorbs the ultraviolet, such as Wratten 25
|
||
or 2E improves sharpness with almost all lenses.
|
||
Also, printing oolor film onto color film, or BEéW film onto
|
||
color film, there is color reproduction advantage to using
|
||
a UV filter.
|
||
Some color rawstooks have such filtration built in, some don't,
|
||
Even printing color film onto B&W film there is tonal advantage
|
||
to using a UV filter.
|
||
IR FILTER A filter which absorbs (or reflects) the infrared keeps much
|
||
of the light energy which would heat the original but not
|
||
contribute to the photography, off the original. Thia filter
|
||
must be located between the lamp and the original.
|
||
Printing Kodachrome original onto color film, there is color
|
||
reproduction advantage to using a filter which reflects the
|
||
far red (past 670nm) and near infrared. Printing other color
|
||
originals there is color reproduction disadvantage to using
|
||
a filter (such as many heat filters) which remove the far red.
|
||
GREEN FILTER Printing B&W to B&W with a nOn-apochromatic lena, a green
|
||
filter can improve sharpness.
|
||
FILTER LOCATION The spectral effect of a filter on the photography is
|
||
the same wherever it ia looated between the lamp and
|
||
the rawatock. The optical effect of a filter can't be
|
||
good, #o it ought to be located on the illumination side
|
||
of the original rather than on the image-formation side.
|
||
(There, flawe in filters are harmless. A color filter
|
||
may even be perforated to reduce its effective saturation. }
|
||
EXPOSURE In optical printing as in original photography, the expoaure ig
|
||
adjustable, and a necessary consideration. But there is a
|
||
differenoe. The natural scene may exhibit an immenes brightness
|
||
range, from the brightest light sources (and secondary sources --
|
||
reflections) to the darkest light sinks. The film original
|
||
4s limited in brightness rangs, between the clear of the base
|
||
and the maximum density of the amulsion. This could be an
|
||
11 atop range for some color reversal fllms, but only about
|
||
6 atops for a negative original.
|
||
The exposure problem in original photography is to decide what
|
||
portion of the immense brightness range to capture on the filn.
|
||
The exposure problem in optical printing is to decide how to
|
||
capture on the print film the whole of the original image range.
|
||
EXPOSURE ADJUSTERS SHUTTER SPEED 4 variable speed motor or gearing can
|
||
give a few atops of adjustment. Brevity is limited by
|
||
inertia. <A single-frame mechaniem cannot be expected to
|
||
complete a cycle in less than about .! second. Slow
|
||
running ie unlimited, but emulsions miarespond to very
|
||
~ long exposures, losing sepeed and gaining contrast.
|
||
|
||
10
|
||
With the variable shutter the shutter speed (the time
|
||
the light etrikes a point in the frame) may be adjusted
|
||
although the printer camera runs at just one speed.
|
||
Exposure can be adjusted over eeveral stops with the
|
||
variable shutter. Brevity 16 limited by the ehutter
|
||
mechanics which must give equal even exposures at the
|
||
smallest shutter angles.
|
||
To cut exposure by 1 etop using the Variable shutter,
|
||
halve the shutter angle. To cut another stop, halve
|
||
it again.
|
||
Uaing the variable shutter for exposure adjustment makes
|
||
4te use for fades or dissolves inconvenient.
|
||
LENS APERTURE This is a Billy way to adjust exposure.
|
||
Changing lene aperture changes picture sharpness.
|
||
Except for fine expoeure adjustments (t# stop) the
|
||
lens ia beet left at ite sharpest opening.
|
||
(For exposure testing and other dirty work, lens
|
||
aperture 1a a handy exposure adjuster.)
|
||
LAMP VOLTAGE This ie the classical way to adjust
|
||
exposure for B&W printing. But it introducee eolor
|
||
changee. Also, modern halogen lamps lose life at
|
||
prolonged low voltages. Voltage adjustment is a
|
||
practical means for fine exposure ad juetment.
|
||
Dropping the voltage 10% reduces the light about t
|
||
stop while changing the color about CCOSY¥+CCOecM.
|
||
POLARIZERS Two polarizere, one rotatable, i8 a cute
|
||
way to adjust exposure. But sheet polarizere get
|
||
hot and have short lives in the optical printer.
|
||
Only very expensive ones can maintain color neutrality
|
||
i over a 10 stop adjustment range, and it is ead to
|
||
fry then.
|
||
ND FILTERS These grey filtere are the preferred
|
||
way to adjust exposure.
|
||
.30 of Neutral Density equala one etop.
|
||
Neutral Density values add as filters are stacked.
|
||
Thus an ND.10 filter + an ND.20 filter + an ND. 50
|
||
filter works like an ND.60 filter, and thie cuts
|
||
the light 2 atope. Etc.
|
||
.10 of Neutral Density equals 1/3 stop.
|
||
A clear glase or film may be ueed ae an ND.035 filter
|
||
E for finer exposure ad justmente.
|
||
Long, graded ND filters allow econtinuove expoaure
|
||
adjustment.
|
||
|
||
ND filters of higher value become hotter and have
|
||
ehorter lives. In a pack of ND filters, lower values
|
||
should go toward the lamp. Past .60 it makea little
|
||
difference.
|
||
Wratten #96 gelatin ND filtere are expensive because
|
||
of their optical quality, unnecessary Where they are
|
||
located in the optical printer.
|
||
Lee theatrical filters #209, #210, and #211 are good
|
||
for ND.30, ND.60, and ND.90 and cost 1/100 as much as
|
||
Wrattene.
|
||
There are glass ND's, both absorptive and reflective,
|
||
of great permanence. Also, developed B&W filmes, fine
|
||
halftone screens, etc. can be used as ND filters.
|
||
SPECIFYING EXPOSURE The many variables of exposure include:
|
||
1. the type of original filn and ita pictorial qualitie
|
||
2. the type of print film (and if a lab stock its
|
||
batch number)
|
||
3. magnification
|
||
4, lena aperture
|
||
5. diffuser (if any)
|
||
6. lamp voltage
|
||
7. shutter angle
|
||
8. non-ND filtration
|
||
as well as 9. ND filters
|
||
FILM SPEED ABA 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 atocks. For many printing filme 4SA and related
|
||
values are undefinable.
|
||
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.
|
||
RIGHT EXPOSURE Working in revereal there 18 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.
|
||
(Even if the optical print must be intercut with the
|
||
original, so that the two must produce matching release
|
||
print, it doeen't follow that the two must match, and
|
||
they shouldn't.)
|
||
Starting from reversal camera original the beet reversal
|
||
. optical print ie typically a littie (about ND.20) Garker
|
||
than the original. This avoids the print film's toe.
|
||
, The best reversal optical print of thie will mateh it.
|
||
And so on.
|
||
|
||
t2
|
||
Starting from negative camera Original the best interpositiy
|
||
print has some density in the highlighte. The beat
|
||
internegative ts a little darker than the origtnal négative.
|
||
A further interpositive would best match the firat one, etc.
|
||
GENERATIONS Gammas multiply. For example, @ gamma 1,5 Original printed
|
||
onto gamma 2 etock resemblea a ganna 3 original,
|
||
in @tany-generation pictorial Optical printing a chain of
|
||
B400e 1 a@tene results in unchanging picture contrast.
|
||
393 and CRI are gamma | color reversal stocks. 7243 18 a
|
||
Fanma ? color negative atock. PXR and 7361 are ganna 1 B&W
|
||
revergal etocka. 7235 16 a gamma t Baw negative stock.
|
||
For B&W negative there is the option of alternating gamnas
|
||
above and below 1 -- 7366 with gamma 1.4 and 7234 with Fanme
|
||
-? -- and multiply out to 1.
|
||
There are no available reversal stocks with Gamma less than 1,
|
||
For color reversal ECO, until ite disappearance in 1985, was a
|
||
favorite gamma 1! camera stock and ECO--ECO--ECO--atc. was the
|
||
classical printing scheme. ECO--7399--7399--stc. was A eimilar,
|
||
possibly better echeme. For each, only the release print would
|
||
be on higher gamma stock. No present color reversal scheme has
|
||
that advantage. Higher gamma original VEF-=-7399-=-7399--etc,
|
||
18 a printing scheme. For this, the release print too will be
|
||
on 7399. Original Kodachrome follows the VHF achene.
|
||
7399 stock misbehavea with exposure times longer than about
|
||
-1 second.
|
||
For B&eW reversal PXR--PXR--PXR--ete. is the classical printing
|
||
Scheme. PXR--7361--7361--eate. 4a a Similar, slightly better
|
||
scheme. For each, unless an Cpal @iffuser ia used the effective
|
||
gamma is much greater than t.
|
||
For color negative ECN--7243--7243--ete. is the classical
|
||
printing acheme. The alternating positive and necative pictures
|
||
allow different manipulations. Optical printing from picture
|
||
negative requires unusual cleanliness, to avoid white apecke
|
||
in the final image. A food atratery La to make the odd printing
|
||
atepa quick and simple, perhape even contact printed.
|
||
The shortcut acheme for eolor negative ECN--CRI--CRI--ete.
|
||
comprises only picture negatives.
|
||
For B&W negative there ia a shortcut schene BWN--7361--7361--ete
|
||
Tonal degradation sometimes confused with contrast increase
|
||
may be due to misexposure, or to impossible exposure (as when
|
||
the print film lacks the exposure range to handle the denaity
|
||
range of the Original). Then picture falls on toe or shoulder
|
||
; and ia tonally compressed.
|
||
|
||
13
|
||
Through generations graininess semi-adds. The grain of the
|
||
original is in part added to the grain of the print stock.
|
||
The print may thue look leas grainy than the original, or
|
||
more grainy, or juet differently grainy.
|
||
Through generations sharpness diminishes. The unsharpnegs of
|
||
the original joins the unsharpneas of the lens and the unsharp-
|
||
nesa of the print stock, in the print. Sharpnesa may be
|
||
boosted, however, by boosting contrast.
|
||
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 thie medium the original, intermediate, and
|
||
final pictures are all of the same eize, made in similar ways,
|
||
of similar materials. Besides the practical economy, there
|
||
ia 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.
|
||
|
||
BELLOWS FORMULA Exposure way change with magnification. A "bellowa
|
||
forgula" works for moet printer lenses and most 1illuminatio:
|
||
systema. It prescribes...
|
||
|
||
magnification compensation
|
||
M=.13 add ND.50
|
||
M=.18 add ND. 46
|
||
M=.25 add ND. 41
|
||
M=,35 add ND.34
|
||
M=.50 add ND.25
|
||
M=.71 add ND.14
|
||
M=1 normal
|
||
‘ _ remove ND.16
|
||
er i M= remove ND.35
|
||
Binsup Sper i -# N=2.8 remove ND.56
|
||
M=4 rencve ND.S80
|
||
M=5.7 remove ND1.04
|
||
u-8 remove ND1.31
|
||
FADES Pictures like things fade in many ways. Brightness fades are
|
||
Gradual exposure changes leading to black, or, starting from black
|
||
leading to normal exposure.
|
||
|
||
o fade out with a positive original, exposure is decreased, either
|
||
ty adding ND filtera to the normal pack or by closing the shutter,.
|
||
some more each frame. When the ND added is somewhat darker than
|
||
the black of the original, this counts as exposure cutoff.
|
||
|
||
|
|
||
14
|
||
To fade out with a negative original, with the same effect,
|
||
exposure is increased, by subtracting ND filtere from the normal
|
||
pack, some more each frame. When the ND subtracted ia somewhat
|
||
darker than the black of the original, thia counts as exposure
|
||
cutoff. Thia fade is imposaible without an abundant reserve of
|
||
printer illumination. The normal pack must contain enough ND for
|
||
the removal. 4n alternative is discussed below after dissolves.
|
||
& fadein i6 the simple reverse of a fadecut.
|
||
LOG FADE The traditional fade ia made from a positive and ta logarithmic.
|
||
With ND fliters a log fadeout is made by adding each new frame
|
||
a ocertain amount more ND. With revereal orlginal, 5.00 added
|
||
about completes the fadeocut. For example, a 350 frame log
|
||
fadeout ie made by adding .10 of ND each frame.
|
||
For every ND value there is an equivalent shutter angle. Chart
|
||
C below shows the equivalences and ia adaptable to any shutter,
|
||
A Variable shutter could be callibrated in both degrees and
|
||
ND's. But toward the bottom of Chart C the angular settings
|
||
are too close for ordinary wariable shutters. Long smooth
|
||
log fades from reversal original are difficult with variable
|
||
ehutters. However, from interpositive original a fade ia
|
||
finished at about ND1.60, avoiding the difficulty.
|
||
BOLEX VARIABLE SHUTTER 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 degreea. Fine
|
||
ecallibration should not be attempted for there
|
||
is play in the mechanisaa.
|
||
LINSAR FADE The linear fadeout, compared with the log fadeout of the
|
||
sane 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. For aimplicity, take a jinear fadeout to be conplete
|
||
at O°. 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. The fade
|
||
is planned as if for a variable shutter and then ND
|
||
equivalents are found in Chart C.
|
||
|
||
OTHER FADES any gradual transition between full exposure and black
|
||
4s an exposure fade. The "look", and perhaps the "meaning",
|
||
of a fade depends on how the expoeure changes with the frames.
|
||
|
||
FaDES IN ORIGINAL A fade made fron a scene looks distinctly different
|
||
|
||
from one made from a film image of the scene if the
|
||
scene containge bright highlights. Made from the acene,
|
||
the highlights shine on when the remainger of the scene
|
||
|
||
~ is practically black. Made from the film, the highlighte
|
||
follow the other light parte of the picture.
|
||
|
||
sak] C NEUTRAL DENSITY AND EQUIVALENT SHUTTER ANGLE i
|
||
PERCENT DEGREES DEGREES
|
||
NEUTRAL OF FULL FOR 170° FOR °
|
||
DENSITY SHUTTER SHUTTER SHUTTER
|
||
0.00 100% 170°
|
||
205 89.1% 152°
|
||
«10 79.4% 135° ae
|
||
-15 70.8% 120° =
|
||
~20 63.1% 1079 oo
|
||
225 56.2% 96° —==
|
||
30 50.1¢ 95°
|
||
235 44.7% 76° <==
|
||
»40 39.8% 68° —
|
||
45 35.5% 60° Sell
|
||
50 31.6% 54°
|
||
~55 28.2% 48°
|
||
60 25, 1% 43°
|
||
-65 22,48 38°
|
||
-70 20.0% 34° ___
|
||
75 17,84 30° ae
|
||
.80 15, 8% 27°
|
||
~85 14.1% 24°
|
||
90 12.6% 21,40
|
||
-95 11.2% 19,19 =
|
||
1.00 10.0% 17.09
|
||
1.05 8.91% 15.2°
|
||
1.10 7.94% 13.59 aa
|
||
1.15 7.052 12.0° =
|
||
1.20 6.31% 10.7
|
||
1.25 5.62% 9.6°
|
||
1.30 5.01% 8.59 =a
|
||
1.35 447% 7-60 aaa
|
||
1.40 3.98% 6.8
|
||
1.45 3.55% 6.0° — an
|
||
1.50 3.16% 5.40
|
||
1.55 2, 52% 4,89 _
|
||
1.60 2.51% 4,30
|
||
1.65 2.24% 3.80
|
||
1.70 2.00% 3.45
|
||
1.75 1.78% 3.0 _ a
|
||
1.80 1.58% 2.7° ss
|
||
1.85 1.41% 2,4°
|
||
1.90 1.26% 2.149 _
|
||
1.95 1.12% 1.91° ____
|
||
2.00 1.00% 70° [==
|
||
2.05 891% 1.52° ____
|
||
2.10 ~ 794% 1.359
|
||
2.15 . 708% 1, 20°
|
||
2.20 .6312 1.079
|
||
2.25 562% .96° ____.
|
||
2.30 501% 2 Ee
|
||
2.35 AATE 76 ____
|
||
2.40 3985 68° o——— 7
|
||
2.45 -355% -60° —————
|
||
2.50 3162 «540 ———F
|
||
2.55 . 2828 48° ——s
|
||
“ 2.60 251% 43° —=
|
||
2.65 2248 38 a
|
||
2.70 . 200% . 34°
|
||
2.75 .178% 30° _—
|
||
2,80 158% . 27° =
|
||
2.85 141% . 24° Sica
|
||
|
||
a
|
||
i **Refer to this chart when slanning linear fades and tissolveg++
|
||
Equivalent Shutter Ovenines
|
||
+N. % of Full Shutter 190° 130° Tz=7
|
||
00 100 180 130 25
|
||
05: 89.1 140 115 209
|
||
.10 79.4 143 193 15¢
|
||
215 70.8 127 92 15e
|
||
~ .20 *3.1 114 82 148
|
||
225 54,2 101 73 132
|
||
-.30 (1 stop) 50.1 90 65 117
|
||
—.35 44,7 80 53 195
|
||
—.40°' 39,8 72 52 94°
|
||
~.45 35.5 Ad 46 33
|
||
~ 2 50: - 31.6 57 41 74
|
||
-.55 28,2 51 37 Ae
|
||
~ .60-- (2 stops) 25.1 45 33 5a
|
||
~ 45 22,4 40 29 53
|
||
~.70 ° 20 36 26 A7
|
||
~.75 17,8 32 23 42
|
||
“.80-: 15.8 29 20 37
|
||
™~,BS 14.1 25 18 33
|
||
(2 FR > ™~.90 (3 stops) 12.6 23 1A 30
|
||
~.95 11.2 20.2 15 26
|
||
™ 4,00: - 10 18 13 24
|
||
ee ™1.05 8.91 16 12 21
|
||
ad 1.10: - 7.94 14.2 19 19 |
|
||
1.15 7.08 12.7 2 17 |
|
||
. ™“1.20.-(4 stops) 6,31 11.4 3 15
|
||
1.25 5.62 10.1 7 13
|
||
~. ™1.30° 5.01 9 7 12
|
||
13s 4,47 B 2 11
|
||
“1. 40 3.98 7.2 G 9
|
||
™ 1,45. *~ 3.55 6.4 5 3 5
|
||
1.50 (5 stops) 3.15 5.7 4 7 .
|
||
~~
|
||
2:00
|
||
|
||
16
|
||
|
||
IMAGE SUPERPOSITION 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.
|
||
|
||
Pictures A & B combined by...
|
||
|
||
(1) Double exposure from positives. The print film
|
||
is eared twice, once from A's positive, once
|
||
from B's positive.
|
||
|
||
(2) Double exposure fron mepetizes: The print film
|
||
Ts expose wice, once from A 8 negative, once
|
||
from B's negative.
|
||
|
||
(3) Bipack. Two films, either A's and B's positives,
|
||
Or é6lee A's and B's negatives, are inserted
|
||
together in the printer gate. The print film
|
||
4s exposed once, from this pair.
|
||
|
||
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&W the differences can be described by how tones
|
||
|
||
combine.
|
||
|
||
With (t}, lightness dominates. Where one tone
|
||
|
||
combines with another tone the result is nearly
|
||
|
||
the lighter of the two tones.
|
||
|
||
With (2), darkness dominates. The result ia nearly
|
||
|
||
the darker of the two tones.
|
||
|
||
———=> With (3), there is contrastification which complicates
|
||
the tone combination. If a bipack is examined ray
|
||
(unprinted) wherever both images are clear the bipaer
|
||
4a clear. Wherever either image is black the bipack
|
||
4s at least that black. Wherever both images are
|
||
black the bipack is doubly black. The bipack, whiob
|
||
appears dark, has a tonal range doubling that of the
|
||
single images. The bipack is wprintable in toto.
|
||
|
||
To abstract a pioture from the unprintable bipack
|
||
|
||
printing exposure is typically increased 1-4 atops.
|
||
|
||
With 4 stops increase, where clear and black eoincide
|
||
|
||
printe as a dark grey would—not 4 clear domination
|
||
|
||
of either lightness or darkness. With 2 stops increase
|
||
|
||
there is darkness domination.
|
||
|
||
GaMMa ¢ BIPACK If the bipack is printed onto gamma $ material, to reduce
|
||
the contrast to normal, it is a true tonal blender,
|
||
without dowinance, of the two images. As the graphs below
|
||
show, the gamma # bipack ia the mean between the type (1)
|
||
|
||
~ and type (2) double exposures.
|
||
|
||
INCIDENTALLY A type (3) of a type (1) and a type (2) le just a type (3)
|
||
|
||
again.
|
||
|
||
r. a a
|
||
17
|
||
|
||
Four idealized graphs summarize the three basic types of
|
||
|
||
superposition and the gamma # bipack.
|
||
|
||
Example: 4 has density .75 and B has denaity 1.75 in one
|
||
place. From the first graph, the double exposure
|
||
from positives has density about 1.0 in that place.
|
||
|
||
as Pous exfosup am Foss as BiPACK. (10 Come
|
||
|
||
as Me de
|
||
|
||
is ib fo]
|
||
|
||
je ia
|
||
|
||
cy -
|
||
|
||
e
|
||
|
||
5 = io LS ts a: Sg = he Lf wt as
|
||
|
||
Ly Ltt L Pi 5 A ‘a 2 2 APPA L elie
|
||
|
||
= i wat
|
||
|
||
ae Le
|
||
|
||
‘ly \ WX |
|
||
|
||
Fo x7 14 ie to as 85 e 2 4 20 oe
|
||
|
||
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 4 bean-splitter, the two exposures
|
||
are simultaneous. Kither way, the two filma can be
|
||
independently adjusted for exposure, filtered, etc.
|
||
|
||
For a bipack it doesn't matter which film ie 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. Ir
|
||
|
||
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.
|
||
|
||
18
|
||
When filmwe will be physically bipacked they should firet
|
||
be wiped with a lubricating film cleaner. This ie good
|
||
practice for all optical printing when delicate originals
|
||
receive heavy handling.
|
||
|
||
EXPOSURE COMPENSATION For superpositions from random pictorial originale:
|
||
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 Bame as a
|
||
single normal exposure of A.
|
||
For bipacks there ie no recipe. Expoaure adjustment
|
||
ie extremely dependent on whioh 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% 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 $ bipack of
|
||
picture A with picture A is the same a6 picture .
|
||
SPECIAL ORIGINALS 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
|
||
48 different, perhaps unnecessary.
|
||
With special, rigged, originale superposition is not
|
||
image combination in the earlier sense but image
|
||
apportionment -- implantings and supplantings.
|
||
The rulee of tone combination etill apply, but trivially,
|
||
and a eimpler logic prevails.
|
||
Double exposing from positives, where one image is
|
||
——_>> black the other image appears, unaffected by the doubie
|
||
exposure, Where one image is very light it appears,
|
||
hardly affected by the double exposure.
|
||
Double exposing from negatives, where one image (the
|
||
picture, not the film) ie clear the other image appears,
|
||
unaffected by the double exposure.
|
||
Bipacking, where one image is any even tone, the other
|
||
image appears, unaffected exoept for brightness. The
|
||
clear parts of one film are windowa for the other film.
|
||
But it is possible, with enough extra exposure, to
|
||
force one image through the blackened window of the other
|
||
The most extreme cases of rigged originals involve high
|
||
contrast masks, Gisoussed below.
|
||
TEXTURING In~a bipack, an image.of a plain white eurface, showing just
|
||
= ite texture, imparte this texture to the other image.
|
||
|
||
19
|
||
|
||
MULTI-EXPOBURE Triple, quadruple, etc. multiple exposures are made
|
||
|
||
similarly to double exposures. If there would be 5
|
||
exposurea from the same or nearly the same original,
|
||
|
||
then each should receive 1/5 normal exposure. From
|
||
|
||
Chart C, 1/5 of full shutter equals ND.70 compensation.
|
||
|
||
eat lizely the originals are special, and the compensation
|
||
ess,
|
||
|
||
MULTI-PAck Tripacks, quadripacks, etc. are unmanageable in simple optical
|
||
|
||
printers. For suob effects intermediate prints must be made.
|
||
For example, to quadripack A,B,0,D make printed bipacks of
|
||
|
||
A with B and C with Dand bipack these two printe. The order
|
||
of the originals doesn't matter.
|
||
|
||
NATURAL SUPERPOSITION Of the three types only (1), the double exposure
|
||
from positives, corresponds to possible camera origina:
|
||
4n original double exposure made from two real scenes
|
||
la practically the same as a printer double exposure
|
||
made from positive images of the acenes.
|
||
|
||
Type (2), the double exposure from negatives, ia
|
||
|
||
an artifact of the "log linear" response of negative
|
||
films.
|
||
|
||
Type (3), the bipack, is an artifact of the
|
||
transparency of film images, at least one of then.
|
||
Type (1) 16 nature's super. Preasing one eyeball
|
||
produces such superpositions.
|
||
|
||
FLASHING Double exposing an image with no image -- sere light -- lightens
|
||
(or with colored light and color print filma, colors) the blacks
|
||
and darker tones while having little effect on middle tones
|
||
and even lese on lights. It is8 not a true method of contrast
|
||
reduction.
|
||
|
||
Sepia toning can be simulated by both color flashing and color
|
||
filtering when printing B&W original onto color reversal print filr
|
||
A healthy yellow, magenta, or cyan flash when printing onto color
|
||
reversal film yields, respectively, the yellow, magenta, or cyan ~
|
||
image, as if this dye layer were prised from the original film.
|
||
There ie no photographic method for unflashing a flashed image.
|
||
There is image addition (double exposure} and image pultipliocation
|
||
(Dipack) and even image division (bipack of positive with
|
||
negative), but no image subtraction.
|
||
|
||
CONTRAST ADJUSTMENT Gammas add or subtract in a bipack, so bipacking
|
||
|
||
can adjust contrast. A bipack (printed gamma 1 or
|
||
Viewed raw) of an original with its duplicate is
|
||
like a double contrast original. <A bipack of an
|
||
original with its low contrast negative is like
|
||
|
||
~ a darkened reduced contrast original.
|
||
“fhe bipack of an original with ite high contrast
|
||
negative is like a Sabattier solarization!
|
||
|
||
20
|
||
COLOR IMAGE SUPERPOSITION There are the same three basic types.
|
||
Double exposure from positives gives additive
|
||
color mixture.
|
||
Bipacking gives so-called subtractive color
|
||
mixture. Uwnen bipacking color negatives the
|
||
extra orange mask should be neutralized by
|
||
filtering.)
|
||
Double exposure from negatives gives something
|
||
else.
|
||
For greys in the two images, combination 1s
|
||
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.
|
||
The dyea in Wratten CC filters Y,H,C are
|
||
aimilar to those in color filma. Film colora
|
||
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.
|
||
Exapple 1: Image & is orange (CC200Y+CC100M)
|
||
Image B ts blue (CCtO00M+CC200C)
|
||
Double exposure from poaitives gives a raspberry
|
||
color (CC7OM+4ND. 30)
|
||
Double exposure from negatives givee a fairly dark
|
||
greyish green (CC7OY+CC70C4ND1.00)
|
||
Bipack, with 3 stop exposure compensation, gives a
|
||
middie grey (ND1t.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.5
|
||
Double exposure from negatives givee black (CC30Y+ND2. 20
|
||
Bipack, with 3 stop exposure compensation, gives
|
||
brown (CC9OY+NDt.60)
|
||
Example 3: Image A is a flesh (CC30Y+CC20M+CC10C)
|
||
Image B ia sky (CC6OM+CC80C)
|
||
Double exposure from positives gives Neola yecckeeoosec)
|
||
Double exposure from negatives gives cc18y+CC45M+Cc58C
|
||
Bipack, with 1 stop exposure compensation, gives
|
||
( CCSOM+CC60C)
|
||
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.
|
||
|
||
DISSOLVES A diesolve begins with one picture. Then a second picture
|
||
gradually appears, all over the frame, shares the frame with
|
||
the firat picture, and gradually replaces it.
|
||
|
||
The traditional dissolve i8 a simultaneous (double exposed)
|
||
|
||
linear fadeout of the firat 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 shuttere. At
|
||
|
||
each frame the ahutter 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 dlasolve.
|
||
|
||
It 18 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 veraa.
|
||
|
||
A diseolve 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.
|
||
|
||
EFFECTS DISSOLVES Diseolves are great emoothers, not only between scenes
|
||
|
||
but between "“effecta".
|
||
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 forma a pictorial
|
||
bridge from positive to negative. The bridge ia of
|
||
strange stuff. The all-grey picture is not on the way.
|
||
The mentioned strange atuff is reminiscent of Sabattier
|
||
solarization again. The double exposure of a picture
|
||
with its negative, preferably onto contrasty filo,
|
||
gives a reversing tonality: Dark things become lighter
|
||
than middle tone things, which remain darker than light
|
||
things.
|
||
|
||
FADES FROM NEGATIVE If a diasolve ie 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 ta required. The clear film ia
|
||
faded in approximately logarithmically, and the
|
||
negative is faded out couplementarily.
|
||
|
||
22
|
||
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
|
||
cco filters and ND filitere.
|
||
A CCY-- filter worke roughly like an ND.-- filter on
|
||
just the blue part of the spectrum, while not affecting
|
||
the rest of the epectrum. 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
|
||
4a roughly CC30Y+CC30M+CC30C. This elimination ie
|
||
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 ehould
|
||
be done in earlier rather than later printing stepa-
|
||
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 pear-neutral mid-tones.-
|
||
Jointly varying cC and ND filtration, a long series of test
|
||
exposures ia made. The developed print is compared with the
|
||
original. Simple reeemblance to the original isa less desirable
|
||
than preservation of crucial qualities of the original. The
|
||
decieion of "right exposure” ies not easy.
|
||
It te tempting to shorten the teet by varying CC and ND separately.
|
||
An ND value ia fixed and the cc's varied. A CC value ia fixed and
|
||
the ND's varied. This maken decisions the more difficult,
|
||
reguiring beat-color judgements on off-brightnees pictures and
|
||
beat-brightness judgements on off-color pictures. Thies leada
|
||
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 co's.
|
||
At each line make a seriée of ND Tariations surrounding
|
||
an initial guess of the right HD. Ferbaps the guess -.59,
|
||
-.40, -.30, -.20, -.10, the guese itself, +-10, +-20, and +.
|
||
The series is lopsided because the oC filtrations are all
|
||
added to the CC guess.
|
||
The 37 CC variations X the 9 ND variations = a 335 frame
|
||
teat.
|
||
Y MM C
|
||
0 0 0
|
||
0 0 10
|
||
0 0 20
|
||
‘ 0 0 30
|
||
’ 0 10 0
|
||
o 10. «610
|
||
|
||
0 10 20
|
||
© 10 30
|
||
0 2 0
|
||
© 20 10
|
||
0 20 20
|
||
0 20 30
|
||
o 30 O
|
||
0 30 10
|
||
0 30 2
|
||
0 30 630
|
||
10 0 oO
|
||
10 0 10
|
||
10 0 2
|
||
10 0 30
|
||
10 10 0
|
||
10 20 0
|
||
10 30 0
|
||
20 0 O
|
||
20 0 10
|
||
20 0 2
|
||
20 0 30
|
||
20 10 0
|
||
20 20 0
|
||
20 30 «~O
|
||
30 0 O
|
||
30 0 10
|
||
30 0 20
|
||
30 O 30
|
||
30 10 0
|
||
“ 3 20 0
|
||
_ | 30 30 0
|
||
|
||
_—-_. =_ —
|
||
£4
|
||
+H
|
||
39M
|
||
. 2QM ,
|
||
QM . wee
|
||
° toy 1pc
|
||
2Qy ‘ 29c
|
||
aaa ° ’ aac
|
||
12 . * +C
|
||
A joint color and brightnesa 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 10-20-50 net
|
||
usable when there is fair confidence in the initial guess.
|
||
When there is better confidence in the guegse the teat 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 testa 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 adjustmente, CCO5
|
||
and CCO25 are too likely to be defeated by the processing lab.
|
||
When there is little eonfidence in the guess the 10-20-30 net
|
||
could be modified te a eearser 20-40-60 net (by doubling «11
|
||
Values, including the ND variations). This is still a 37 line
|
||
teat. 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 noy,
|
||
or to do a coarse test and alwost deteruine 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.
|
||
|
||
| 25
|
||
CC PACK REDUCTION any combination of CCY, CGM, CCC, and also CCB, cca
|
||
CCR can be reduced to a nearly equivalent combination
|
||
of just two of the firat 3 kinds and some ND.
|
||
Method: 1, change CCB to COM+CCC
|
||
change CCG to CCY+ccc
|
||
change CCR to CCY+CCM
|
||
|
||
ce. add together all CCY
|
||
add together all CCM
|
||
add together all ccc
|
||
|
||
3. Whichever of the three kinds has the malilest
|
||
total in step 2 is eliminated. én equal
|
||
anount of ND ia added. An equal amount is
|
||
subtracted from the regaining two kinds in
|
||
atep 2.
|
||
|
||
4. count the number of CC filtera 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+CC1IO0C+CC40R
|
||
|
||
1, pack becomes CC20Y+CC1OC+CC40Y+CC40M
|
||
|
||
2. pack becomes CC60Y+CC40M+CC10C
|
||
|
||
3. pack becomes CC5OY+CC3IOM+ND.10
|
||
|
||
4. pack becomes CCS5OY+CCA3OM+ND.14
|
||
|
||
HIGH CONTRAST PRINTS The techniques for printing onto high contrast
|
||
(masking) stocks are little different from those
|
||
for printing onto low contrast (pictorial) atocks.
|
||
The high contrast stock itself is the tone-difference-
|
||
exaggerator. —
|
||
One grey tone in the original may print unchanged
|
||
in the high contraet 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 criginal
|
||
become much darker in the hicon.
|
||
Tones much lighter than the one in the original become
|
||
~ black in the bhicon.
|
||
|
||
r — ——_
|
||
26
|
||
|
||
HICON EXPOSURE Thie makes exposing a hicon print from a continucue tone
|
||
original fairly critical. 7362 stock can be developed to
|
||
about gamma 4. Then with 1¢ etops extra exposure, regions
|
||
ef the original which previously printed clear onto 7362
|
||
eould 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 ie somewhat dependent on procesaing tine,
|
||
temperature, and agitation. It is strongly dependent
|
||
on UV filtration.
|
||
|
||
An exposure test is made by printing the eriginal onto
|
||
the hicon stock at a long series of closely apaced
|
||
exposures. The original and print-wedge are kept for
|
||
reference.
|
||
|
||
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 tonea in the first
|
||
hicon print clear or black in the second hicon.
|
||
But thie three atop range resulted from a 3/4 atop
|
||
range in the original, That 1s, all but a tiny
|
||
part of the picture should now be either clear
|
||
|
||
or black.
|
||
|
||
If the firat hicon had gamma 4, the éecond 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 ie derived from the continuous tone original.
|
||
It 18, practically, all clear and black.
|
||
|
||
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 atep, becoming a black and clear speckle.
|
||
To avoid speckle, exposure must be adjusted at an early
|
||
etep, before there is black and clear in the pattern, to
|
||
force the whole area to clear or to black.
|
||
|
||
To promote speckle, exposure 18 adjuated to hold the area
|
||
in the greys through several eteps.
|
||
|
||
, a
|
||
27
|
||
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 ¥31):
|
||
|
||
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.
|
||
|
||
LOGIC OF MASE 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 Rulea,
|
||
|
||
whieh refer to the whole of the mask (all printin;
|
||
|
||
eteps being exact 1:1):
|
||
|
||
1. The negative of the negative of A is the
|
||
Bame 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.
|
||
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 overexposurees Which swell and spread
|
||
the areas of black image. With the first 2 or 3
|
||
etops of overexposure the spread is microscopic.
|
||
Beyond this the edges of areas give out and
|
||
positively bloon.
|
||
- Bloom ie pretty. It is the result of both lena
|
||
diffraction and film halation. It hints that
|
||
' lurking under every sharp exposure, many stops
|
||
dowm, is a secondary pattern of exposure spreading
|
||
over the whole frame.
|
||
|
||
28
|
||
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 unneceseary.
|
||
Not quite black blacks indicates a safe exposure,
|
||
and all that is needed if there will be a later
|
||
hicon generation.
|
||
MASK AND COUNTERMASK A bigh contrast negative print made at exact 1:1
|
||
from a high contrast mask is ite "countermask".
|
||
Exact 1:1 reproduction (diecussed above in AIMFRAME)
|
||
ie the first requirement for good fitting of the pair.
|
||
Having achieved exact 1:1 reproduction, perfectionists
|
||
will notice that image spread causes a alight misfit
|
||
of maek 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 fil;
|
||
2, to make the coOuntermask with apread as usual
|
||
while also remaking the mask, by printing it
|
||
firet with excessive (double) apread and then
|
||
printing that with usual spread;
|
||
3. to use reversal processed hicon as discussed
|
||
below.
|
||
Changing the magnification cannot correct spreading.
|
||
REVERSAL/NEGATIVE FITTING A beautiful trick allows well-fitted mask pairs
|
||
without exact 1:1 setup. They are made by
|
||
exposing two lengthe of 7362 from the same hicon
|
||
original using the identical (undisturbed) setup.
|
||
One length is proceseed negative and the other ia
|
||
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
|
||
4s equal to the slight apreading of clear in the
|
||
reversal print.
|
||
Thia mask and countermask might fit each other
|
||
exactly, but if the setup wasn't exact 1:1 they
|
||
wlll 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
|
||
systen. If the printer gate has a different
|
||
eystea, then that perfection will soon be lost.
|
||
|
||
29
|
||
This problem arose above in AIMFPRAME. Simply,
|
||
an optical printer with unmatched camera and
|
||
gate registration mechanisme, however excellent
|
||
they may be, is doomed to registration defects
|
||
in moat affects.
|
||
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 softnese
|
||
A method involves making gamma 1 positives from a hard-edged
|
||
mask pair, printed out of focus. If gamma 1 reversal (7361)
|
||
aoe not have sufficient black, negative-positive (7234-7366)
|
||
oes,
|
||
Inetead of actually making soft-edged masks, the hard-edged
|
||
masks, defocused, can function as soft-edged. Since the
|
||
uBual use of mask paire is in bipacke 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" filme are separated.
|
||
IMAGE MARRIAGE Wipea, inserts, saplitscreens, colored titles, etc. are all
|
||
exanples of the same technique. One picture is bipacked
|
||
with one mask and thie 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
|
||
maek 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 proceeda
|
||
gradually from all clear to all black (the other from all
|
||
black to all clear) defines a wipe. "Proceeds gradually”
|
||
ie subject to interpretation.
|
||
Pretty nearly all image marriages fall into three categories;
|
||
= 1 aah,
|
||
rae a py i
|
||
i WH a, —
|
||
\ J
|
||
I II IIt
|
||
I. One region takee ita shape from the things pictured within it.
|
||
II. One region takes ite shape from the things pictured around it
|
||
IIIf. One region takes its shape from some not-pictured thing.
|
||
|
||
30
|
||
MASK BLACKNESS For successful image marriage the black of the hicon wask
|
||
should be about 3 stops darker than the black of the picture
|
||
Which will f1l1 the black region.
|
||
HICONS FROM COLOR ORIGINALS 7362 film is sensitive to blue light only.
|
||
For example, it cannot "see" the brightneas
|
||
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 filtere as
|
||
needed to separate the colors.
|
||
If two colors are different, there ia a filter
|
||
Which will make them record differently on
|
||
panchromatic film.
|
||
Thie is simpler when the two colora are on fila
|
||
than when they are in the natural world, because
|
||
film colore are spectrally aimpler. 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
|
||
ie greatest (in the Y, the M, or the C) chooge
|
||
the complementary filter (B,G,R, reapectively)
|
||
in a atrong (non-CC) version.
|
||
Example: Color 1 ia a flesh (CC30Y+CC2OM+CC10C)
|
||
Color 2 is eky(CCOY+CC60M+CC80C )
|
||
The greatest difference is in the cyan
|
||
4S). so a red filter such as Wratten
|
||
29 1e used to separate this flesh
|
||
and aky.
|
||
HICON PROCESSING Negative
|
||
1. Develop 6 minutes in D-11 @70° with continuous agitation.
|
||
2, Rinses 30 seconds in stopbath or water.
|
||
3. Fix 1% minutes.
|
||
(3. 7369 only. Rinse 1 minute in ae Clearing Agent.)
|
||
&, Wash 2 minutes in running water (longer for permanence),
|
||
= 5. Dry.
|
||
|
||
} 31
|
||
Reversal
|
||
T. Develop 6 minutes in modified D-11 (adding eg 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 thie 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 no»
|
||
6. Develop 3 minutes in D-11.
|
||
7. Rinse 30 seconds in etopbath or water.
|
||
8. Fix 1# minutes.
|
||
9. Wash 2 minutes in running water (longer for permanence).
|
||
10. Dry.
|
||
At reversal step 5 the film looks like carved ivory.
|
||
OPTICAL PRINTED RELEASE PRINTS The work of film art olght 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 atripe applied to the
|
||
finished print (preferably in emulsion
|
||
position IIIa).
|
||
|
||
RITUAL AND ART Two mediums may allow production of exactly the same
|
||
range of objects, but by different means. Then different
|
||
objecta will in fact be made in the two mediums and the
|
||
occasional identical objects will have different meanings.
|
||
Know what medium you are in.
|
||
|