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Eclair Cameras: Digitizing/Reversal Film

Eric and I exchanged a few emails a while back because I have been contemplating building a similar rig to digitize from 16mm film. Right now I've run out of money and steam, but hope to resume the project in the future. It's not an urgent issue with me - just something I'd like to tinker around with. With that in mind I'm not going to try to engineer anything terribly sophisticated - I'm more interested in cobbling together a "proof of concept" apparatus that is no more complicated than is necessary. Having worked as an animator/FX guy on a few films, I am familiar with the process of scanning 35mm film to digital files, pulling those files into a computer and manipulating them, and then outputting them back out to film. It occurred to me that if there were an inexpensive way to scan my 16mm neg to digital, I could manipulate that material in any number of ways, creating a digital intermediate that could then be output to just about any medium existing now or yet to be invented. I worked on one title sequence for a feature film that combined archival footage, horrible 1970's-era video, graphics, stock footage, the whole lot, and which was then output to scope (widescreen) format, so I have some experience mixing and matching different source material in the digital realm. Like Eric, my basic idea is a kind of hybrid digital/optical printer, using a digital still camera at one end and some kind of frame-by-frame movement and light source at the other. Very Rube Goldberg-esque, but what if it worked?

For the film movement, I thought I'd take an old spring wind 16mm camera with single frame capability (probably a Cine Special), remove the shutter disk and file out the gate to accommodate an area bigger than the Super-16mm film area. With the magazine modified, film can move between a pair of aluminum split reels along a fairly straight path, to minimize wear on the neg. BTW, if anyone has a junker Cine Special they want to get rid of, let me know. I just need the "front end" - no mags or lenses.

If you're thinking that a funky 1940-something camera mechanism can't provide the level of registration accuracy required for an optical printer, I'm sure you're right. My feeling is that it only has to be reasonably steady, because it is possible to stabilize the image in the digital realm to an extremely high standard. I think the "tracker" function in After Effects corrects to 1/64,000th of a pixel. All that would be needed would be a stable point - a tiny pinprick of light adjacent to the film - for the computer to use as a reference. Shouldn't be a problem.

A lightsource and diffuser need to be placed behind the film (possibly relayed along a tube to a 45-degree mirror) - something like an old-fashioned rotoscoping arrangement. My thought was to use an AC-powered strobe as the light source (I'm trying to source from stuff I have lying around where possible) as the output is extremely consistent and the recycle time, when the power is dialed down to about 150 watt-seconds, is extremely quick. Eric has suggested an LED light source, and I have seen some interesting LED units intended for use in optical experimentation that look like they would be excellent. The LED's have the advantage of being quite small (one only needs a postage-stamp size light source, after all). For the camera, I was thinking of the Nikon-based Fuji S2, principally because of the Nikon lens mount. There are several professional-level digital SLR's out there with resolution that exceeds what is necessary for 35mm output. Looking at an old cheat sheet from my animation days, I can tell you that the standard output size for my digital files ("flat" 1:85 ratio, for North American theatrical projection) was 1828 x 988 pixels - well within the range of the Fuji S2, Nikon D100, etc. For purposes of this contraption, the size of the image sensors in these cameras is not an issue - in fact the larger 24 x 36mm sensor of some cameras may be a liability.

A conventional bellows unit goes on the camera and a high quality enlarging lens, such as the Apo-Rodagon, goes on that. The camera/bellows/lens unit is mounted on a translation stage with micrometer adjustment of position along the X, Y, and Z axis. At such extreme magnification focus is achieved by moving the entire camera/lens rig along the Z axis. The camera/lens rig, the "movement" apparatus, and the feed and take-up reels would get bolted to a heavy base with vibration-dampening feet. Obviously, this arrangement does not allow for such niceties as a liquid gate (this is definitely intended as a low-cost alternative to going to an expensive service bureau and spending thousands of dollars, so there are trade-offs), and dust could prove a problem. I wonder if it wouldn't be possible to enclose everything in a big plexiglass box - sort of a miniature clean room - with some kind of anti-static air cleaner scrubbing the atmosphere inside. As I think Eric has mentioned, a computer could be used to control the whole operation so that it could run unattended. However, I thought I'd do something ridiculously simple, like an AC-synchronous motor driving a cam that would sequentially advance the negative by one frame, fire the digital camera, advance the negative by one frame, fire the digital camera, and so on. A cheesy Veeder-Root or similar counter could count the revolutions of the wheel, thus providing a frame count. I know this is Flintstonian, but I'd like to keep it simple and cheap to begin with - computer control could be attempted after I've determined that the basic arrangement works.

The digital images can be pumped directly via firewire from the camera to a nearby computer - I think this would obviate any concerns about the capacity of the camera's memory device - with each shot being dumped into a different folder as sequentially numbered files. A program like After Effects can be instructed to recognize a series of numbered stills as a sequence, and one can then view them in motion on the computer and can manipulate them in every way imaginable - sharpness, grain suppresion, gamma, saturation, color correction, etc. - as well as resizing, reformatting, letterboxing, compositing, and so on. I've already done a lot of digital scratch removal and "dust busting," so I know that that can be done (laborious but not difficult). Also, anything shot with an anamorphic attachment lens can be digitally "unsqueezed" in the computer. Obviously, too, you can "dump" your shots out to video if you like (maybe to show to investors as a "work in progress"?). Obviously, all of this requires an investment in computer equipment and software, but I suspect that a lot of us have access to most of what we would need.

As for Eric's desire to shoot on BW reversal film, that I don't understand. I suppose he's going for that "soot and chalk" look, but wouldn't that be easier to achieve - and more forgiving too - in the digital realm? I recently watched "Pi," which was shot on BW reversal film, and was again struck by how shitty it looked. The contrast is way too high, with almost no midtones. This look may have suited "Pi," but I found it painful to look at - too much information lost in the shadows, and the highlights all blown out to solid white. I think shooting BW negative and capturing the broadest possible range of image information would be better. Obviously, you "invert" the image in the computer to provide a positive, and set levels to compensate for the negative's base mask. From there, to get the "soot and chalk" look, one could just dial up the contrast digitally by adjusting the characteristic curve. Very easy in After Effects, and completely reversable too. Just my thoughts.
- Ian Marks

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