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This topic comprises 3 pages: 1 2 3
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Topic: BH perforations on release prints
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John Pytlak
Film God
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Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000
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posted 01-18-2005 12:11 PM
Kodak VISION Color Print Film 2383 is available with BH-1866 and BH-1870 perforations, primarily for "background plate" projection applications that use pin-registered movements. Of course, 35mm release prints normally use film perforated KS-1870:
http://www.kodak.com/US/plugins/acrobat/en/motion/catalog/printfilm04.pdf
http://www.kodak.com/US/en/motion/support/h1/sizesP.shtml#perfs
quote: Perforations Why All the Sizes and Shapes? In the early days of 35 mm motion pictures, film perforations were round. Because these perforations were more subject to wear, the shape was changed to that now known as the Bell & Howell (BH) or "negative" perforation (Figure 41). This modification improved positioning accuracy and was the standard for many years.
During this time, 35 mm professional motion picture cameras and optical printers were designed with registration pins that conformed to negative (BH) perforation. To this day, newly designed professional equipment incorporates registration pins conforming to the negative (BH) perforation. In 1989 Kodak introduced a stronger version of the Bell & Howell (negative) perforation. The radius of each corner was rounded by 0.005 inches. This small difference is almost imperceptible visually, but adds strength where the perforation is most vulnerable to tearing during stress periods while being transported through equipment. This is especially true during highspeed photography. This corner radius change does not necessitate any equipment change worldwide, and yet improves product performance.
Another Bell & Howell perforation performance improvement was introduced by Kodak in 1989. This is a reduction in perforation-dimension tolerance from the ANSI specifications. This tighter tolerance format is used where film registration is very critical, such as in travelling matte photography or separations. The tighter tolerance perforations are standard on all Kodak 16 mm camera films and some 35 mm films.
The high shrinkage of older films on nitrate base made the negative perforation a problem on projection films due to excessive wear and noise during projection as the sprocket teeth ticked the hold-back side of the perforations as they left the sprocket. The sharp corners also were weak points and projection life of the film was shortened. To correct this, a new perforation was designed with increased height and rounded corners to provide added strength. This perforation, commonly known as the KS or "positive" perforation, has since become the world standard for 35 mm projection print films.
During the period when the production of color prints involved the multiple printing of separation negatives onto a common print film, a third design, known as the Dubray-Howell perforation, was introduced. It had the same height as the negative (BH) perforation to maintain the necessary registration but had rounded corners to improve projection life. This perforation is still available for special applications on certain films. Because shrinkage in current films is low, the shorter perforation height poses no projection wear problems. In 1953, the introduction of Cinemascope produced a fourth type of perforation. This wide-screen projection system incorporated 35 mm film with perforations that were nearly square and smaller than the positive (KS) perforation. The design provided space on the film to carry four magnetic sound stripes for stereophonic and surround sound.
Perhaps the print you had was originally made for a pin-registered application, and they kept the print for theatrical use. Or someone grabbed the wrong cans of raw stock.
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Tao Yue
Expert Film Handler
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Posts: 209
From: Princeton, NJ
Registered: Apr 2001
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posted 01-18-2005 10:11 PM
That was a very limited release of Doctor Zhivago in 1999. As long as Warners was paying the overhead of a small print run, why not spend a bit more to ensure uninterrupted stock? After all, Sony struck dye-transfer Technicolor prints of Funny Girl, and IBTech is even more expensive for short print runs.
Too bad, I'd like to have seen Zhivago in 35. With 2383 print stock and DTS, it'd be like seeing it in 70 back in 1965, what with the improvements in color saturation, grain, steadiness, and sound.
Would be interested in seeing info about these sorts of one-off (or dozen-off) prints in Feature Info. But the print's probably out of your hands by now.
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John Pytlak
Film God
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Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000
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posted 01-20-2005 12:49 PM
I don't know the storage history of the negative and masters for "Dr. Zhivago", but there are many examples of original and duplicate elements from that era surviving quite well (e.g., the recent new prints of "Sound of Music", "Hello Dolly", "Patton", etc.). Processing (especially washing out residual chemicals like thiosulfate) and storage conditions (SMPTE Recommended Practice RP131, Standard ANSI/NAPM IT9.11) often have more to do with long term image stability than the choice of film stock.
quote: Leo Enticknap In fact that would probably exacerbate the fading, thereby requiring heavier correction when printing seps for preservation.
Since dye fading is usually manifested as a loss of contrast or buildup of stain, a denser, "richer" negative is usually better. There's more image to begin with, and less unreacted coupler chemistry left in the film.
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Bill Carter
Expert Film Handler
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Posts: 162
From: Minneapolis, Minnesota
Registered: Sep 1999
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posted 01-21-2005 11:39 AM
Is it possible this one was accidentally printed on some type on low-con stock intended for telecine?
Not too long ago, I had my hands on one of the 35's of Dr. Zhivago struck for the 1993 reissue (has Turner Entertainment in the end credits). Although that print was badly beaten up through mishandling, the color, contrast, and grain looked okay. Not breathtaking, but okay.
According to Dick May at Warner, original camera negative was used for those prints, with the exception of parts of reel one, and ALL of reel eleven, which had been damaged and replaced with dupe material many years before. New wet-gate interpositives and dupe negs were struck in '93 from that material.
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