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Topic: More d-cinema morons

John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-15-2004 08:43 AM

It's usually not the numbers of prints, but the "shortcuts" labs are forced to use to meet tight release deadlines.

In particular, it is well known that printing a short pitch original to a short pitch raw stock on a continuous contact printer is less than optimal because of possible slippage in the printer, resulting in loss of sharpness and possible unsteadiness. Continuous contact printing is designed to print a short pitch original to a long pitch raw stock, and excellent quality can be obtained, even at the very high printer speeds used for release printing.

Ideally, the short pitch original negative should be printed to make a long pitch master positive. The long pitch master positive is then printed on a slower step printer using registration pins to make the short pitch duplicate negatives needed for the final release printing to long pitch (KS-1870 perforations) print film. Or the short pitch duplicate negatives can be made directly from a Digital Intermediate. But step printing and laser recording are relatively slow, compared to continuous contact printing, requiring more time (days rather than hours) to make multiple duplicate negatives for a worldwide release --- time that a tight production schedule may not allow.

http://www.kodak.com/US/en/motion/support/h1/printing.shtml

http://www.kodak.com/US/en/motion/support/h1/sizesP.shtml#p

quote:
Optimum Pitch for Printing.
Continuous printers used for motion picture film are designed so that the original film and the print raw stock are in contact (emulsion-to-emulsion) with each other as they pass around the printing sprocket, with the raw stock on the outside (Figure 43). To prevent slippage between the two films during printing (which would produce an unsharp or unsteady image on the screen), the original film must be slightly shorter in pitch than the print stock. In most continuous printers, the diameter of the printing sprocket is such that the pitch of the original must be 0.2 to 0.4 percent (theoretically, 0.3 percent) shorter than that of the print stock. With nitrate film and early safety film, this condition was achieved by natural shrinkage of the original during processing and early aging. However, the substantially lower shrinkage of present safety films makes such a natural adjustment impossible; therefore, film used as printing originals is now manufactured with the pitch slightly shorter than the pitch of the print film For 35 mm film, the pitch dimensions are 0.1870 inch (4.750 mm) on print film and 0. 1866 inch (4.740 mm) on original film; for 16 mm film, they are 0.3000 inch (7.620 mm) on print film, 0.2994 inch (7.605 mm) on most camera film.