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Shoot 3 Perf And Print 4 Perf

1st September 2005

Might be shooting a 35mm short film soon and have a question about doing it in 3 perf.

I know there is not really an issue if going DI or straight to the small screen but what about ending up for normal 4 perf cinema screening projector?

What is the exact route of this and if it's possible why don't everyone do it? Can I shoot 3-perf 1.85:1, give the off-line edit keycode to the neg cutter and then from have a straight optical done to 35mm 4 perf or am I missing a link here?

I'll be talking to a lab in the next few days but thought I'd get some more knowledge here first.

Flemming Jetmar
London DP

Yes, you can optically blow-up 3-perf to 4-perf, most likely by making a color-timed 3-perf IP and then using an optical printer to make a 4-perf IN.

You'd have to do your answer printing in 3-perf, which may be a problem for your lab in terms of screening the print.

David Mullen, ASC
Los Angeles

Yes, you can do a 3 perf optical to 4 perf. You take a generational hit as with any optical and very few people have the gear to do it. I believe Technicolor in Rome has a printer that will do this.

Best regards,

Anders Uhl
Cinematographer, NY
The DoP Shop

Your neg matcher and your lab may very well have difficulties in cutting the neg precisely to match the edl. Keykode numbers are every foot which is 21 1/3 frames in 3-perf. Very few software systems exist to handle this fractional count precisely and reliably. (Don't be fooled by software which has only been used to extract complete takes).

Also the lab will probably have difficulties in cuing light changes on the frameline - as most color analysers and printers are locked into 4-perf framecounts.

An alternative is to cut the neg with handles (so that exactly-placed light changes aren't critical), make the IP and then have the matcher cut the IP to the correct length - but you've still got problems cutting accurately.

Then of course you've got to find a lab with a 3-perf optical printer to make the 3-perf to 4-perf "blow-up" in the DN stage. They do exist, but aren't common.

The post production costs might well escalate to the point where you lose your savings on camera neg stock and processing.

Dominic Case
Atlab Australia

Dominic Case wrote:

>Very few software systems exist to handle this fractional count precisely >and reliably.

While this is technically true, Avid systems can and do handle 3 perf key numbers quite well, and have for a number of years. They utilize the Evertz convention of marking each key number with a "perf marker" that indicated whether the dot is on perf 1, 2, or 3, and they get around the 1/3 frame issue by counting 20 frame offsets and 21 frame offsets as needed. This counting scheme became a defacto standard a number of years ago and has been used ever since. The most recent versions of Cinema Tools for Final Cut Pro use the same convention.

Since between Avid and Final Cut you've covered probably 98% or more of feature editorial, I don't see the software as a problem at all.

>Also the lab will probably have difficulties in cuing light changes on the >frameline

This is, to some degree, true, but to my mind it also has everything to do with the very narrow frame lines the 3 perf format has, unless you're doing a 2.35 extraction. Of course, you could cut A/B ribbons, but this is going to add to both the complication and the cost, although it would keep some of the optical work quite a bit cleaner.

The last time I was in Rome, Technicolor was in the process of setting up a negative cutting system specifically for 3 perf, largely at the behest of Vittorio Storaro. I don't know if that project was completed, in part because Vittorio's most recent project (the 2nd version of Exorcist: The Beginning) wound up being finished via a digital intermediate in Los Angeles.

>Then of course you've got to find a lab with a 3-perf optical printer to >make the 3-perf to 4-perf "blow-up" in the DN stage.

Technicolor can do this in Rome and Los Angeles, as can numerous other labs, particularly those in Europe.

>The post production costs might well escalate to the point where you >lose your savings on camera neg stock and processing.

Contrary to the tone this post might seem to have, I would probably be the last person to advise anyone to finish a 3 perf production using a traditional film post path. There are numerous issues in shooting 3 perf, not the least of which is that it's very unlikely that every shot used in the production will actually be 3 perf.

High speed photography, second unit, stock shots, inserts - some or all of these will likely wind up being in 4 perf format. Because of this, and the issues mentioned above, I would opine that 3 perf is an excellent format for achieving full 35mm film quality without compromise while also saving on film costs, particularly for 1.85 or flat 2.35 framings - but should really be used only when a DI is the intended finishing solution.

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

I can't contest anything that Mike says about the solutions to the 3-perf issues : he is correct every time. But you still have to ask the questions at the lab - only a few can (or will) handle 3-perf.

However, just as Mike takes a positive tone then says he wouldn't advise anyone to use 3-perf for a film finish, I would reinforce my more cautious tone for the same reasons. Very often the reason for exploring 3-perf is because the budget is extremely tight, and filmmakers don't always, as a result, have access to late versions of FCP or Avid, nor will Technicolor Rome be their obvious choice of lab (unless they are in that part of the world).

Digital Intermediate makes many of the 3-perf problems go away, and also allows you to intercut with 4-perf material quite seamlessly. It's a much more appropriate post pathway (than film/optical duplication) for a 3-perf project where the budget does allow it.

Dominic Case
Atlab Australia

Thanks ... I'll come back with what the labs here in London say.

Flemming Jetmar
DP London

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