Contact vs Optical Intermediates
>Published : 11th February 2005
>I have a 35mm feature that has finished the Answer printing process, and I'm now proceeding with the IP/IN.
>The feature was shot soft-matte framed for 1.85. I'm interested in putting a hard mask on the IN (around 1.60 as per suggestions received on this forum previously to allow for showing in Europe as well). My concern being the projectionist, specially in the theatres I'll be showing in, not masking the image properly.
>My question has to do with the masking process. Do I have to make the IN optically for this to happen? I don't have access to a "C" roll with a mask burned in (any idea if I can get one somewhere?) - and wanted to know if there was an alternative way to do this in contact printing?
>In summary, I'd like to learn a little bit more about the making of an IN via contact vs optical printing, with reference to the masking issue, cost, quality, etc.
>Thanks for any info!
Standard SMPTE 195-2000 suggests a "hard matte" with an image height of at least 12.83mm :
>"To help ensure correct vertical centering (framing) of the projected image, hard-matte printing may be used in producing the duplicate negative used for release printing of theatrical prints. A hard matte with an image height of at least 0.505 in (12.83 mm) may be used for all style A aspect ratios (1.66:1 or greater). Note that prints intended for a style C aspect ratio (1.37:1) will normally have an image height of at least 0.630 in (16.00 mm) as specified in SMPTE 59. In all cases, the framelines on the print shall essentially be opaque."
Eastman Kodak Company
>No need to use optical printing to get a mask: the frameline mask can be burnt in when the IP is made, and there is a good chance that your lab already has a roll (it's hi-con or title stock with a black frame and clear frameline). If not they should be able to make one to the dimensions that you specify (see John Pytlak's reference on this). The lab has to expose this roll quite accurately, to ensure sufficient black to fog out any trace of the image without getting image spread which softens the edge of the mask, but it can be done.
>The alternative method, that does involve optical printing, is to put a hard mask into the gate of an optical printer, and make the DN optically, resulting in clear frameline edges on the DN.
>In general, optical stages either in IP or DN, can increase the resolution of the final result IF the lens is good enough_ but a poor lens will be worse than using contact printing for that stage. Usually optical printing takes a lot longer and the lab will charge more for it. It's the method that is necessarily used for anamorphic squeezes from super 35 though.
>Finally, consider whether you really need it. Out of the hundreds of widescreen (1.85:1 or so) films distributed each year, very very few go to the trouble of masking the prints. Are you assuming that the projectionist will look at the screen and notice if the film is racked incorrectly?
>One additional advantage of a pin-registered optical or step contact printing stage between master positive and duplicate negative is that you can avoid printing a short pitch original to a short pitch raw stock on a continuous contact printer. Continuous contact printers provide optimum sharpness and steadiness only when printing a short pitch original to a LONG pitch raw stock.
>Printing a short pitch original to a short pitch raw stock on a continuous contact printer can result in slippage between the films during printing, possibly leading to some sharpness loss or unsteadiness. That is why Kodak VISION Color Intermediate Film 5242/2242 and EASTMAN Fine Grain Duplicating Positive Film 5366 are available with both long and short pitch perforations:
>(Optimum Pitch for Printing)
EI Customer Technical Services
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Eastman Kodak Company
Rochester, New York 14650-1922 USA
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