1691 lines
62 KiB
Plaintext
1691 lines
62 KiB
Plaintext
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= NOTES ON OPTICAL PRINTER TECHNIQUE
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Magnification 1 Fadea in Original 14
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Blowup.& Reduotion 2 Chart C: Neutral Déneity and
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Blowup Sharpness 2 Equivalent Shutter
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Printer Lenses 3 Angle 15
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Optical Zoom 3 Image Superposition 16
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Lene Aperture 3 Gamma # Bipack 16
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Focusing 4 Incidentally 16
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Focusing Aperture 4 Exposure Compensation 18
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Focusing Precision 4 Special Originals 18
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Focusing Target 4 Texturing 18
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Depth of Field 4 Multi-Exposure 19
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Bolex Priam 4 Multi-Pack 19
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Bolex Groundglass 4 Natural Superposition 19
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Defecus 4 Flashing 19
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X-Y Adjustment 4 Contrast Adjustment 19
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Exact 13:1 5 Color Image Superposition 20
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Ainframe 5 Weighted Double Exposures 20
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Franelines 6 Dissolves 21
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Emulsion Position T Effects Dissolves 2}
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Time 8 Fades from Negative 21
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Fancy Freeze 8 Color Exposure 22
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Fancy Slow 8 Testing 22
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Diffusers 8 CC Pack Reduction 25
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UV Filter 9 High Contrast Printa 25
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IR Filter 9 Hicon Exposure 26
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Green Filter 3 Contrast Building Steps 26
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Filter Location 9 Hicon Speckle 26
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Exposure 9 Tone Isolation 27
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Exposure Adjusters 9 Logie of Mask Combination 27
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Specifying Exposure 11 Image Spread and Bloom 27
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Film Speed 11 Mask and Countermask 28
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Right Exposure 1 Reversal/Negative Fitting 28
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Generations 2 Feathered Maska 29
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Bellows Formula 13 Image Marriage 2g
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Fades 13 Mask Blacknesé 30
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Log Fade 14 Hicona from Color Originals 30
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Bolex Variable Shutter 14 Hicon Processing 30
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Linear Fade 14 Optical Printed Release Prints 31
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Other Fades 14 Ritual and Art 31
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i on
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NOTES ON OPTICAL PRINTER TECHNIQUE
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DENNIS COUZIN
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March 1983
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An optical printer 18 a device for photographing the frames
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of one film sco as to make another filn.
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e 2 - . ,
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I
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Cc
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It consists essentially of @ camera (C) connected by a
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bellows (B) to a lens (L) aimed at a film in a gate (G) illuminated
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from behind by a lamp (I).
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The camera and gate each have motorized intermittant filin
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movements so that any frame of the "original" film can be
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conveniently photographed onto any frame of the "print" filo.
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The camera can be an ordinary cine camera, less its lens,
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and the gate can be an ordinary cine projector, less its lens.
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Ideally they have identical syatemsa of film registration, aa if
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one Were the lens’ image of the other. The lens can be any
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bellows mountable lens. Ideally it ie specially corrected for
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the amall and nearly equal sizes of this object and image.
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The camera and the lens can elide independently to and fro
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the film gate. Thie adjustea the magnification and the focus of
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the photography.
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MAGNIFICATION If the lens is (nominally) midway between the films
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when one is focused on the other, then the magnification
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is 1. At M=1 (also called 1:1} the whole of the original
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frame 1s photographed at a size which fllis the whole
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of the print frame.
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i ) oY ?
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If the lens 18 moved closer to the gate, then the
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camera must be moved back, farther from the gate,
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_ to keep the one film focused on the other. Then the
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Copyright (1983 by Dennie Couzin
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r
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2
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magnification is greater than 1. At M>1 a part of the
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original frame is photographed at a size which fille the
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whole of the print frame.
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If, starting from the 1:1! setup, the lene is moved
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farther from the gate, then the camera must also be
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moved back, farther from the gate, to keep the one film
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focused on the other. Then the magnification is loser
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than 1. At M<1! the whole of the original frame is
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photographed at a size wohich does not fill the whole
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of the print frame. The remainder of the print frane
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46 filled with a photograph of the gate as it surrounds
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the original frame (ideslly perfectly black).
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6 y
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For each position of the lens there is exactly one
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correct (focused) position for the camera. But for
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each position of the camera (except the 13:1 position)
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there are two correct positions for the lens. One
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gives M>1, the other M<}.
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BLOWUP & REDUCTION The printer gate may hold Smm film and the printer
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camera 16mm, or vice versa. With ap M=2 setup an
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Sum original frame 18 photographed onto a whole
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1énm frame. With an M=¢t setup a whole !6um original
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frame is photographed onto an Smm frame. Conversion
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between any two film gauges 4s possible thia way,
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provided the frames have the sane proportions, as
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Sum, super San, 16mm, and some 55ma do.
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BLOWUP SHARPNESS A 16mm picture of a flea can be just as sharp ae
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@ 16mm picture of an elephant. Fut & \é6an picture
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of an Smm picture cannot be expected to be as sharp
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as a t6mn picture of a 16mm picture. Pictures differ
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. from thinge in having very limited detail. The 16as
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blawup, even if it preserven all the pictorial detail
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of the mm original, spreads it out, so the blowup
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ie less sharp absolutely than the original.
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,
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3
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Under extreme magnification -- a microscope objec
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eould be the printer lene -- pictorial detail i: diffuse
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and the underlying natural thing, the enulsion, is all
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that could be photographed sharply. But the grains are
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too small to be sharply imaged with light. Here even
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the natural thing haa been photographically exhausted,
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an 8mm original blown up to 16mm and projected will
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appear sharper than the sane 8mm original optically
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printed onto Smm and projected. If the blowup optics
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are good thie is even true when the 1:1 printing is by
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contact. Likewise for 16mm to 35mm. (This ie all due
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to the print film being in effect twice as sharp and
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half as grainy in a bigger frame.)
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PRINTER LENSES A lens well-corrected for M-1 is less well-corrected
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for M=? (or M=t). A lene Wwell-corrected for M=2 is
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leas wall-corrected for M=4 (or M=%). Etc. (Floating
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elementea improve this.) A lens well-corrected for M=1
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for a larger format is lees than ideal for M-1 for a
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smaller format. With such specialization (and expense)
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in optical printer optics what ie the hope for the
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$50 SOmm enlarger lens, optimized for M=.1 and much too
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large a format? Wot bac, provided the sharpest aperture
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ie found and heeded and focusing technique is eine.
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Aleo, for Mé! ano asyunetrical lens should be mounted
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the right way, which is usually with its smaller glass
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facing the smaller image.
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A very sharp cheap printer lens is the Canon Macrophoto
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35mm £/2.8.
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OPTICAL ZOOM Optical printers do not use soom lenses, although they could.
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An optical printer toom is made by moving the camera and
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lene each frame, so as to vary magnification while holding
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focus. It is a dolly shot! A dolly abot is equivalent
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to a toom for a flat subject.
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Geometrically this zoom oan be identical to a zoom had
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it been made in the original photography. It can also
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be deviant, by tracking not to the center of the frame.
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Pictorially the zoom gets grainy, showing that it was
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not made in the original photography.
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Rather than focua at each frame, camera am lene positions
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can be precharted for, say, every 10th frame, and the other
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positions interpolated or computed. On the J-E, counting
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the turns of the lead screw ie a means of repeatable
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positioning. A follo¥-focus sechanian is @ boon to optical
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Z£oons.
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The rate and course of s00ming is a factor of style,
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as it is in original cinematography.
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LESS APERTURE” For picture taking the printer lens should be at whichever
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aperture gives the sharpest pictures. This 4e found in
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teste. If a lens must be atopped down past f/8 to reach
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optimum it is a terrible printer lene.
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F
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4
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FOCUSING Printer focusing procedure is different at different magnifi
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At 1:1 the camera, not the lens, 4e moved for focusing,’ Gulp)
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at magnifications greater than about 1.4 18 it better to nove
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the lens for focusing.
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Near the t:1 setup lens motion has no focusing effect. With
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the camera fixed in its 1:1 position lens motion: adjusts
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magnification between about M=.96 and M=1.04 (at f/5.6).
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FOCUSING APERTURE With all but the best optical printer lenses either
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(1) foous at the taking aperture or (2) foous at a
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larger aperture and then shift focus by a pre-established
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distance before taking. This "fudge-factor" is found in
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film teate.
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FOCUSING PRECISION Especially when focusing stopped dowm, focus many
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times (perhaps 20) and set an average position.
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FOCUSING TARGET Use whatever target ie found eablest to focus on.
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One caution: the fudge-factor is target dependent.
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Very fine resolution targete may require different
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fudge factora than coarser targete do.
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DEPTH OF FIELD at indicated f/5.6 there is already more than enough
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depth of field for a4 bipack, at 1:1. dAleo it ig unnecessary
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to refocus when adding the second film. Likewlee when
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a single film ie reversed’ emulsion to base. At larger
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apertures and at larger magnifications depth of field
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is lese.
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BOLEX PRISM It isn't a worry. There len't a distinetion between RX
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lenees and non-RX lenses for most any lens which will be
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used on a bellows for optical printing.
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BOLEX GROUNDGLASS Only for the best optical printer lenses, which will
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be used at apertures larger than f/4, does the Bolex
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groundglass need to be reset from its everyday position.
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DEFOCUS To throw an image out of focua without changing ite size, if
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printing at i:1, move the camera 4 distance and the lens ¢ this
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dietance, in the same direction.
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X-Y ADJUSTMENT Besides its to and fro movement the lene haa lateral
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movements. These adjust the position of the original
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frame's image on the print frame. For example, if the
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lens is raised a bit...
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5
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At 1:1 moving the lens up a distance d raises the viewed
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field by twice 4d. Likewise for down, right, and left.
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At M>1 lateral adjustment effects a scan of the original
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frame. This is not geometrically equivalent to a pan,
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bad it been made in the original photography,
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On simple optical printers the only lateral ad Justment
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is of the lens (rather than the heavier camera or gate).
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Thie is Geometrically adequate.
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But the J-K adjustments are even too flimsy for a lens.
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It helps, after they are set, to gently tap the lens, ac
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it finds a stable position, and then to readjust if
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necessary, etc., etc.
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EXACT 1:1 The lateral movements of the lens, the to-fro movements of
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the lens and camera, and a tilting of the camera (if necessary)
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allow the optical printer to be set for exact 1:1 reproduction.
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Then the printed image is the same aize and in the same position
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as the original image. If the printer lacks a tilt adjustment
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the oamera may be shinmed.
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AIMFRAME A Special frame is made to guide the exact 1:1 setup. To make
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an "aimframe" use the optical printer camera (though not
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necessarily with the optical printer lens) to photograph a
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target which is epecially drawn to contain detaila exactly’
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coinciding, as seen through the camera eyepiece, with details
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permanently on the groundglass. The photograph made while the
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coincidence is seen is the ainfrane.
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Every groundglass has some permanent detaile, even if only ite
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flaws. The field edge is a poor choice of detail if the mask
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is thick or if the eyepiece is aberrated at the edge. Two
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points of detail are enough for a well~aligned printer, three
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pointe for a suspect one.
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A reticle made on high resolution film may be attached to the
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groundglass to add details. Small patterns of concentric circles
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and other patterns which self-moiré are ideal. also the ainframe
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can be a negative of the fine-patterned reticle.
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For exact 1:1! setup, the aimframe film is registered in the
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printer gate and the printer camera and lens adjusted to
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achieve that same coincidence of details, as seen through
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the eyepiece. Focusing must be completed before the final
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adjustment to the aimframe. It is convenient to incorporate
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a focusing target in the aimframe.
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The aimframe has validity only for the camera in which it was
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made. It does not depend on the accuracy of the camera'a
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reflex viewing eystem, only the stability of the eysten.
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Whenever there is doubt about the validity of the aimfrane,
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such as after a camera repair or because of wear to the filn,
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the old aimframe can be registered in the printer gate, aimed
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on, .and photographed to make a newly valid aimframe.
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For rotoscoping with primitive contrapLions, an aimframe may
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be projected and drawn. This drawing is later used to aim
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the camera (whose aimframe it was) when photographing the
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rotoscoped drawings.
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Fo
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6
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The 1:1 accuracy of optical printing with aimframe setups ie
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limited by 1. the precision in the making and then in the use
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of the aimnfraze,
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2. the precision in the film registration mechanians
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of camera and gate,
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3. only if the two mechanieme are different, the
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precision in the film dimensions (perforation
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and alitting).
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Btep contact printing, Buch 48 by bipacking in the optical printer
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eamera, if & convenient method for making exact 1:1 reproductions.
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It must give exposures which are exact 1:1, but there 18 then sone
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shrinkage in processing. Optical printing with the ainfrane methoc
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compensates for processing shrinkage. Shrinkage errore are too
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apall to matter with simple printers.
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GAMEFRAME A atrip of identical frames, shot in the optical printer camera,
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is cut in two and registered in both the printer gate (upright,
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eanulgion away from lene) and the camera gate (ae it was shot).
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The coincidence of detaile of image and sameframe is viewed throug
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an opening in the rear of a special pressure plate. <A prismatic
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gate focuser may be pubstituted for the pressure plate, but only
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the most positive registration systems will be unaffected by this.
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Only the most solid optical printers will allow loading the carers
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without diesturblog thé setup.
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The sameframe method does not compensate for processing shrinkage.
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FRAMELINES If the camera which made the original film had a frameline
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much higher or lower than that of the printer camera, then
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the vertical adjustment of the lene should deviate from the
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aimframe setup, to compensate for thia. Otherwise the print
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will have a very thick, or even 4 double frameline.
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Sometimes the sole reason for optical printing is to ad juat
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the height of the frameline of an original fim shot with
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a Wayward camera. Sometimes it is to simulate such filo.
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Then the printer camera must have ite frameline adjusted.
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For a Bolex thie is a simple claw exchange (revertible).
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To make a frameline adjustzent, 4f the reflex viewfinder is
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well-set, then even if it does not view the full frame, the
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vertical adjustment can be made until the upper framelins
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just appears, then until the lower frageline just appears,
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and the two adjustments averaged.
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If the reflex viewfinder is untrustworthy, then a camera
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gate focuser can be used. Or thia method: register in ye
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printer gate a bipack of the original with any file ahot in
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the printer camera. Determine how much vertical adjuetaent
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separates their framelines. Make that puch adjustment to
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the aimfrane setup.
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The framelines of the original can always be eliminated
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from the print by setting the magnification slightly greater
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than 1..
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7
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EMULSION POSITION A priori, a film of an alphabet could be any of these
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eight ways.
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F lh
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F Sc G
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¢||e FE
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F F
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Ia Ib IIa IIb
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—__ —— ls
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4 4 5 2
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12) |
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o 4 a
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IIIa IIIb IVa IVb .
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Each sketch showa emulsion facing out. For doubie
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perf film there are only four ways. The a and b ways
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|||
|
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.
|
|||
|
|