VFX History: Optical Printers

[@ShiveringCactus]

In case you're wondering (and to save you pausing), the super fast text reads: This animation is intended to illustrate how a movie camera with film works and it is not intended to be a simulation. An iris controls the amount of light passing through to the film. It can also be used to control access to StarGate Command. A shutter is the device within a camera which controls when a cell of film is exposed, but that element does not appear as intuitive as an iris. Also the iris and/or shutter would both appear inside the camera body, behind the lens, not infront as depicted here. Finally, while the effect of the exposing the negative looks kinda cool (at least I think so), it would most likely not appear in the manner depicted. It would most likely all fade on together with some elements continuing to darken, but this did not look as visually interesting. There - that should address all your notes you may have had, so don’t @ me! Oh...also... thank you for watching!!! And the second one: I've skipping over a ton of information here. Initially COVER MATTEs for the layers are created, then combined to create the INTERMATTE. John Knoll created a BLUE SEPARATION LAYER and then used the GREEN SEPARATION LAYER to create a COLOR DIFFERENCE MATTE for the blue colours, which was then combined with the GREEN SEPARATION LAYER and it is this that is used with the mix of Green and Blue lights. I've not included this here as it is all very confusing and ultimately is just about the refinement process. If you really want a deep dive, it is well worth checking out John Knoll's talk: Old School School 1 - Optical Compositing

[@Jaspax]

Videos like this is what youtube was made for, definitly worth the 16 hour render

[@ShiveringCactus]

Ha! Unfortunately I ended up rendering 3 times, but yeah, it was worth it. Thank you

[@tomkam9783]

This is a really comprehensive breakdown! Great job making this really complex process understandable. I worked at a teeny-tiny optical house in the 90s, first as an intern then became the title designer and built the animation cels and rolls to send to the animation camera. My boss tried teaching me how to use the optical printer and create optical line-up sheets...I was not built for such things. Something you skipped over but worth mentioning just to add more fuel to the confusion of optical compositing - was Density and Color Wedges. Every element that would be added to a composite had to be "Wedged;" a single representative frame from each element would be chosen and printed with every (reasonable combination of printer light - [ oh geez...printers had shutters over the RGB lights in the lamp house to control the lights...by varying the amount of light each color they let through you could adjust the color rendition of whatever you were printing, and where the term Printer Lights comes from]...) When developed, you would have a strip of film with dozens of that single frame printed in all kinds of colors from which someone in authority would have to pick from, BECAUSE, once photographed with the optical printer, your color for the finished composite was locked in (yes, I know...Hazeltine at the lab for color-timing, but you know...brevity!). As for Density, those mattes that are created from the red, green and blue separations when developed are black and clear. Black areas hold out light and clear allow light - and images - to be printed through. But the black areas need to have a certain density to keep light from leaking thru, so there was yet MORE testing involved - using a densitometer - when creating a matte to make sure it will print correctly. Almost final thought...I believe this is where Matte Choking derives from. Increasing or decreasing the exposure time for a matte will make a denser or less dense matte. But it also causes the black area to grow or shrink, one possible cause of matte lines around objects in a shot - and also why you see weird shapes surrounding composited spaceships in old video transfers - it's the difference from "Film Black" and "Video Black." There are a lot of variables. I'll leave it to you to explain why you can't just flip a piece of film over...or why you would flip the camera upside-down to filming reverse action. Thanks again for the memories!

[@ShiveringCactus]

Wow, thanks for these insights. I thought the procedures were complicated before you explain about density, Color wedges and matte choking. Learning about this early VFX time only enhances my appreciation of their work.

[@trackstick_travel]

I designed optical printer control systems. You can use a color wheel that rotates a set of filters to take multiple shots of the same frame. This way you don't have to rewind the film each time a new color is exposed. I hated these machines! They were so cumbersome to work on but I was one of the few people in the world that knew how to repair and redesign them to work better and more efficiently. The "Model C" optical printer was one of the oldest and most reliable. It used a paper tape for color adjustments but wasn't really for special effects. Optical printers weren't just used for special effects. They were used worldwide by Technicolor and Deluxe Film Labs to distribute movie film reels to theaters. If you have any questions, I would be happy to tell you all the various parts of the filmmaking process related to pre and post-production. Burbank, where I reside, is a "coal mining town" where most of this almost 100-year-old technology was and still is occasionally used.

[@ShiveringCactus]

That’s amazing to hear about. And thank you for the offer. What’s the best way to contact you?

[@trackstick_travel]

@@ShiveringCactus email address is on my youtube channel page

[@Jimorian]

During the first showing of Star Wars on television, the differences in contrast in that medium meant that the garbage matts were *painfully* obvious on screen.

[@ShiveringCactus]

I remember - they cleaned it up for the special editions (although the Emperor's slug remained)

[@moocorp]

Finally took that 'I think I get it...' moment from a bunch of reading to the 'I get it now!' elation. Thanks for the work you've done!

[@ShiveringCactus]

Thank you. Like you, I’d had that moment and that’s when I decided to make this video

[@keithartworker]

9:53 Fun fact: There was a mistake for 2 frames where the Millennium Falcon flies past the camera. Two tiny tie fighters were accidently exposed on the Falcon. It's a testament to how much coordination was necessary to pull off such a complicated shot. Thank you for this series. The "bipack" step answers a lot of questions.

[@okankyoto]

Ah yes, this why when working as a compositor, nobody older than me remembers these days with much affection.

[@ShiveringCactus]

I can imagine. I’m in awe of the amount of time, concentration and effort that was needed.

[@MePeterNicholls]

Blimey. That’s a lot of steps and a lot of film!

[@ShiveringCactus]

I know! No wonder there was a push to create computer compositors.

[@filanfyretracker]

And this is why digital combined with NLEs unlocked filmmaking for so many more people, I suspect a huge barrier to shooting even a short film was the cost of film stock. I cannot imagine what effects heavy films must have spent on film alone.

[@VariTimo]

Also back then they used tungsten balanced film for movie which’s blue sensitive layer is about a stop more sensitive than the others. Making the separation clearer and the transition to white easier.

[@Locomamonk]

You need more views, man, this is fascinating!!

[@ShiveringCactus]

I really enjoyed making this video. I’m now working on another similar one

[@VEC7ORlt]

Its kinda sad that all of this knowledge is slowly being lost due to being irrelevant, on the other hand the whole process is insane, so many processing steps, so much film, all this needs to be correctly exposed, aligned, combined, developed, whats even more mind boggling - after all those steps visual fidelity is still preserved!

[@Meteotrance]

The blue color of the blue screen usualy didnt print on a black and white film they use a very high contrast one for making the alpha matte, but some clever guys at Disney Ub Iwerk and Petro Vlahos use to build a more complex system, with sodium vapor light on a blank screen, that make a special orange light that only show to a special prism build inside the camera with two films, one for the color footage and the other that separate the orange one for the alpha mask, it was use on Marry poppins and the Birds from Hitchcock.

[@MarcHendry]

Those pointy "surface gauges" do have a use in stop motion, especially in the days before they had video previews of what they'd already shot. It helps you to track where something was on the previous frame as you're making the new pose. So, like, you point it to the character's fingertip, then when you move the hand, you know where it used to be.

[@into.the.wood.chipper.]

I have never understood how surface gages worked, until you explained it. Thank you!

[@rotcorp]

Came here to say exactly that. Those aren't random bits of garbage... those gauges were an important part of the process.

[@Ybalrid]

This is fascinating

[@faldor]

Brilliant breakdown of how it was done old school.

[@ShiveringCactus]

Thank you

[@DylanReeve]

I honestly struggle to imagine this. It seems impossibly complex. But then I imagine what I sound like trying to explain linear online editing to young editors: "...and then the VTR had a feature called pre-read that would read the video frame and send it out and you could record it back on top of itself. So it would go out through the vision mixer, into the DVE, which would then return on another ME layer and we'd use a downstream key to apply the output of the Inscriber, and it would all go back, via the master matrix router to the VTR's input"

[@ShiveringCactus]

At University we had a Umatic set up. It was so awful. If the tapes were striped completely, you get this warp at each edit point. If there wasn’t enough room for the preroll you’d get everything messed up.

[@DylanReeve]

@@ShiveringCactus Kids these days .. they'll never understand! 😁

[@into.the.wood.chipper.]

​@@ShiveringCactusYeah, you would get tracking jitter and glitches. Striping a tape was really important when editing on VHS cassettes. I used to animate by back-editing to single frames from 2 seconds of recording each move. Switching from play pause to record pause engaged the pre-roll. If you didn't stripe the tape beforehand, the tracking would go crazy and the flying erase head wouldn't know what to do. The pre-roll would also overshoot your mark, so you would end up recording over everything you just shot. And it was even worse if you we're taping over something that had been recorded at a different speed. SLP to SP, for example. We've come a long way from those days, but when sitting down and animating, it feels the same. Stop motion is timeless. You just zone out. It's nice not to have to worry about tracking or tape stretching anymore.

[@arthurdent5536]

Glad I paused that first one, lol. Nice reference hehe

[@ShiveringCactus]

It was so difficult trying to choose what to keep in and what to gloss over.

[@arthurdent5536]

@@ShiveringCactus glad you kept the Stargate haha

[@UNIVERSOENUNACAJA]

I loved this video!! More of these please! ❤ now a lot of after effects and editing procedures make sense to me hahaha

[@ShiveringCactus]

Thank you. I’ve got another few planned. Writing this helped me understand the process too. It’s amazing how complex it all was

[@QUIRK1019]

As I understand it, the huge drawback of this process was that each reproduction added the previous film's grain to the new, quickly leading to a buildup of graininess in composited shots. Apparently, one of Star Wars' big innovations was to use a VistaVision camera for effects shots, running 35mm film horizontally for larger frame size.

[@ShiveringCactus]

That’s the clearest explanation I’ve heard for the use of Vista Vision

[@QUIRK1019]

@@ShiveringCactus Thanks! This video is the clearest explanation of Optical Printing on KZbin!

[@ianhill3446]

Not quite, I believe the team behind 2001 got there first?

[@charlesdorval394]

That was fascinating! Thank you !

[@ShiveringCactus]

Thank you!

[@-RobGPT-]

Working on a super8 star wars fan film, defiantly gonna try and make my own super8 optical printer

[@ShiveringCactus]

Oh wow, really? I hope you’re going to shoot loads of behind the scenes videos (even more so if you do build an optical printer)

[@-RobGPT-]

@@ShiveringCactus This youtube page is for my droid I made mainly, maybe I'll make a dedicated youtube for those project, either way I'll definitely document the process 😅

[@jesseyules]

Very Zen. Thank you!

[@ShiveringCactus]

Namu Amida Butsu

[@RockstarFan-xf8oc]

If I could ask but how did transitions like wipes and dissolves work with an optical printer? Mattes I presume are used in a similar way?

[@ShiveringCactus]

That’s a very good question and one I don’t know the answer to. I’m going to see what I can find out.

[@RockstarFan-xf8oc]

@@ShiveringCactus I would imagine it would be in some way or form. Using a black matte over an image and slowly sliding it over to isolate each part of the image gradually, resulting in a clear celluloid, then using an opposite matte on another background to get a black imprint on that, and then combining the two together would be my own initial thought on how that would work.

[@RockstarFan-xf8oc]

@@ShiveringCactus I mean I don't think Mattes would need to be used, it would probably be just using a black card of some sorts. The dissolve effect would be more complicated though... perhaps different cards again that would match up to where it would dissolve, imprinting it onto the film, and then combining the two again. I don't know about a dissolve, that one is more complicated.

[@ShiveringCactus]

I think this video does a good job explaining (explanation starts at 2:30): kzbin.info/www/bejne/bZXSiZ6CetmEl5Isi=yPAPGIo02jx-Ai7G

[@RockstarFan-xf8oc]

@@ShiveringCactus Yeah nice. I wonder what about the Kurosawa wipes, like in Star Wars?

[@ncot_tech]

Room 1138... I wonder if it has THX audio ;)

[@ShiveringCactus]

Yay! Finally someone spotted the reference

[@kenknight5983]

What about the black bits of an image? If that composited character has black buttons, how do they not disappear when matted out bits of the frame do?

[@ShiveringCactus]

That’s a very good question. My understanding is that even black in the scene still reflects some light, so the film crystals are still affected. If you shot something painted with Vantablack then it’s likely this would appear transparent.

[@kenknight5983]

@@ShiveringCactus Is that why you can make on-screen titles with black edges?

[@ShiveringCactus]

@@kenknight5983 I don't think so (if I understand your question). With digital images, you can "bake" their alpha channels directly into them, so when you add them in video software, you don't have to take care of keying. Even back in the days of optical printers, because the equipment was so precise and because they could spend days perfecting a shot, professionals were able to get blues really close to background blue and still get a key. And they could also darken blacks after keying by re-printing results or adding filters. There's lots of stories out there where VFX guys have figured out ways around the limitations, which only other professionals have recognised it while the rest of the audience doesn't even notice.

[@animaToy]

A link to a schematic of Petro Vlahos color difference matte method laurabrandist94.wordpress.com/wp-content/uploads/2014/03/color-difference-matte-600x774.jpg In a simple term: you actually use negative image to for keying to so dark parts appear on final image

[@iLikeTheUDK]

This is incredibly cool!!! Do you use Blender as well? I think it can let you add some extra polish to the renders that AE alone can't really achieve

[@ShiveringCactus]

Thank you. I know my way around blender, but I wanted the control of timing everything that After Effects gave me. Might be changing up the “archive office” for the next one.

[@rty1955]

I come from a professional broadcast video and also an Emmy Award video tape editor, from a time when color television was in its infancy. I worked on video tape machince since thier birth.The fact the color blue was chosen was because it waa the opposite of skin tone. This is why all chroma key sets simce the early 60s were blue screen not green. The cameras saw all colors the same way as they were setup to render all colors in a linear fashion. Film stock, was different, it was more sensative to green hues, and thats why green is used for film. Film production is very different from video production in this regard. Video M/E switchers were also built differently. Some had regen sync others did not, so mixing true b&w signals with color had to handled specially. For example, diring the vietnam war it was against the law to broadcast a soldier that had any blood on him, in color, so when you broadcast the news that was going to show a b&w clip on a blue screen, you had to send the clip to the switcher along with the burst signal or all hell might break loose on air I used to physically cut 2" quad video tape when i began to edit, them moved up thru to NLE systems. I worked at the largest post facility on the east coast of USA. Our comoany imvented the "pan & scan" mechanism for film chains. We used to xfer all of the movies for Home Box office as well. We used a heavily modified CMX editing system and built out own time code controllers for everything in the house.

[@peterhoulihan9766]

Thanks for the video. I thought I knew how this worked but I was way off. I assumed the red green and blue colours were recorded with different chemicals and they had some kind of chemical bath that could erode green crystals from the negative.

[@ShiveringCactus]

That’s pretty much exactly what I thought too. That feels like it would be so much simpler.

[@sierrafrancesca]

wow!

[@ShiveringCactus]

Thank you. There's a new episode of VFX History dropping Monday actually.

[@tomkam9783]

Thanks!

[@ShiveringCactus]

Thank you! This is my first KZbin Thanks, very cool of you.

[@mhoover]

That shot took 6 weeks to print. It could be done now on a laptop computer in maybe half an hour.

[@ShiveringCactus]

Amazing, isn’t it

[@iivin4233]

It has become clear that Star Wars borrowed its industrial design from the look of that optical printer.

[@turboemerald9228]

imagine if someone tried to do this process in the modern years, it's extremely unlikely, but one could dream.

[@ShiveringCactus]

Optical printers seem to have lasted quite a long time, some people in the comments said they’ve used them. The attention to detail required is astounding.

[@trackstick_travel]

They are still used. There is so much film in the studio vaults that a portion of it has deteriorated to the point that it can't always be put directly on a Telecine for digital transfer. Sometimes it must be restored both physically and chemically. Fotokem, Disney, and a few other labs (very few) in Burbank still have working optical printers but they aren't used as much these days.

[@Dr.W.Krueger]

Something I do not miss; doing optical compositing. :)

[@ShiveringCactus]

I think I have romanticised it a little, because it must have been such a pain lining everything up perfectly

[@alangfp]

WTF? It used to be THAT hard??? wow

[@j.r.shartzer]

Making movies used to be such a pain. I'm not saying modern VFX artists have it easy, but if you made a mistake at any point in this process, you can't undo it. It's just potentially days of labor and costly film gone to waste. I can't imagine what that does to a person's anxiety level as their deadline approaches. ILM has been in a 3-story building for almost 20 years now. It's kind of amazing that they haven't yet had to install nets. Maybe they keep all the really stressful positions at ground level? Maybe they had a safety protocol established so that if George Lucas was on his 5th meeting with you about the fact that he wasn't happy because "Yoda looks more worried than concerned," they just immediately revoked your access to the upper floors. Safety first. Especially when working people to death.

[@lasi_eisbaer]

As a casual VFX interested person, you almost lost me at the end. But cool video though.

[@ShiveringCactus]

Thank you

[@akyhne]

10:07 Blackmagic Fusion 1987. Nuke 1993. After Effects 1993. Sorry, but After Effects wasn't the oldest compositing software.

[@ShiveringCactus]

Oh that bit? That’s clearly a joke. At least I thought it was. Earlier in the video, I used After Effects to illustrate the blue channel, so that was a call back.

[@vaderbase]

Still way to complicated for my mind.

[@ShiveringCactus]

It’s amazing how difficult the process was, and that someone came up with it

[@danim8]

Overall this is a good video, however you assert that AfterEffects was the reason that Optical went to Digital and this is way off. Not true at all. There were many digital tools that preceded AferEffects and for the most part After Effects isn't the tool of choice because it doesn't work well with film. Now before you flame me, It has made huge strides in the right direction and can be used. but it is no where near as robust in it color space or how it "reproduces" the physics and math of light optics in the way Nuke for example does. AfterEffects was created by Cosa not Adobe, and when it was made it was largely influenced by Wavefront Composer which was only available on Silicon Graphics computers and Cosa was trying to bring motion graphics and compositing to the desktop.

[@ShiveringCactus]

Thank you for your kind words. Can I ask, at which point in the video do I assert anything about After Effects?

[@MaximusNYC]

It was obviously a throwaway line -- just a joke.