Steve Switaj

Jason: First, a disclaimer: I have not handled a CP-16 in three decades, I'm just looking at some pictures online. On the other hand, I do build a heck of a lot of film equipment, so maybe I can offer some answers. There are two belts in there, the one on top looks to be a conventional toothed timing belt, and it looks like it probably connects the motor with an intermediate shaft that maybe runs the movement. The second, deeper, belt looks like maybe a PosiDrive belt that connects that first shaft with a couple other functions, maybe mag drive, sprocket, and shutter (?) The first belt, the one on top, looks pretty straightforward. Because the camera was built in the US in the 70's, that belt is probably an XL or MXL timing belt. They both have a trapezoidal profile tooth. XL belts have a pitch of 0.20" or 5.08mm, MXL belts have and a pitch of 0.080", or 2.03mm. MXL's are common in 1/8" and 1/4" width, XLs are usually found in 1/4" or 3/8". There's also a similar metric profile called "40DP" with a pitch of .0785" (2.00mm) but it's fairly rare in the US and I wouldn't expect to see it an an American camera from 1978. If you measure the pitch over say, 20 teeth, you can get a pretty good idea. I don't know where you are - your profile says China. But if you were in the States, I would tell you to go to the Stock Drive Product's website.... https://shop.sdp-si.com/products/synchronous-drive-belts-pulleys-cables/synchronous-drive-belts-pulleys/belts-timing.html?inch_product=1 The good news, it's really easy (again, at least here in the States) to find these in 139 through 144 tooth, 1/8" wide, versions for around $6us. SDP is the obvious go-to but McMaster-Carr also has a wide selection. The second belt is the deeper that one that loops through a couple of sprockets. To me this looks like a PosiDrive. This is a weird belt with a steel core that has molded urethane nubs sticking out on either side. It is sometimes preferred in machines like cameras because it doesn't need flanges, so it doesn't slap as much air with each tooth and runs quieter. Single-core Posidrive belts come in two pitches, 32DP ( 2.5mm ) and 20DP ( 4mm ). You can buy a custom one in any length, but the standard sizes are 130, 140, and 150 teeth, etc. See here on the SDP website https://shop.sdp-si.com/products/synchronous-drive-belts-pulleys-cables/synchronous-drive-belts-pulleys/belts-posi-drive-open-ended.html?inch_product=1

I think realistically about $2000 (US) in the typical B-mount. The super16 conversions or a PL mount goes for a bit more. The downside is that they juuust cover their format at the wide end, there's no room to fudge it if you're on an electronic camera with a bigger sensor. They are really are nice lenses, though. I think they were easily the best 16mm zoom of their generation, literally a half-sized version of Cooke's classic 35mm 5:1. They had that Cooke look, and were a really great lens for portraiture. Plenty sharp enough, but not too sharp, contrasty, enough, but not too contrasty. Kind of like having a wee little bit of black pro-mist in there.

I handled one of these back in the 90's. I walked into a rental place down in Hollywood - maybe Alan Gordons, they were always good for having something unique on the floor - and there was one on a tripod. It was a pretty neat camera. I got the impression that their expected market was less about film production and more about spot news gathering, with built in single system sound, auto exposure, and a fixed zoom lens. But Bolex was just too late. By the late 70's "Film at 11" was still a slogan, but the film in question was now an HL79 and 3/4" u-Matic, which was a lot cheaper, had faster turn-around, and was good enough for the evening news. There just weren't buyers clamoring for a better 16mm eng camera any more. But it was still a cool machine. One neat feature is that unlike the SR's and Aatons I was familiar with, where the mag docks up to the pressure plate, in the Bolex Pro the film was actually pulled deep into the camera body, threaded through the movement, and fed back out into the takeup side of the mag all by itself. If you opened the door and looked inside, you could see how the film path was very tightly controlled to achieve this, like a H16 taken to the next level. Don't know what you were supposed to do if you had to break a roll though, and I wouldn't want to have to clean it out after a jam ....

Indeed it is. And, as an aside, if anybody out there is looking for one to call their own, I just so happen to have one that I'd be willing to make someone a good deal on. Just CLA'd by Ken at Stone Cinema Engineering early this year. Sadly, just don't use it any more.

Ah... and here we hit the nail on the head. The biggest technical problem with building a new film camera is that it's not a technical problem. OK, it's not easy, but technically it's not an insane reach. Yes, we're used to thinking about cameras as precision machines, but from a builders point of view they are actually fairly straightforward. There are only a few areas in the movement and around the mirror box where you have to hold really tight tolerances, and even at, say, +/-.0005” or .01mm that's not all that ridiculous in a good shop with modern equipment (after all, Mitchell and Bell and Howell managed it in 1930 with manual machine tools) The rest of the camera is just film handling. Those parts have “normal” tolerances which should be pretty easy to hold with modern machine tools. And, while modern CNC tools are not the magic bullet some people think they are, they do dramatically change the equation. For example, if you were building a camera in 1960 you would have to find a metal foundry to cast your camera and mag housings, a complex and expensive investment you better get right on the first try. In 2024 it's totally practical (if not especially economical) to turn your CNC milling machine loose to spend 12 hours hogging your housings out of a solid block of stock. And if you have that one client who needs something custom --- well, you can do that with minimal fuss. Many people think the electronics are the most difficult element (I was an electrical engineer before I got into VFX, so I don't share this view), but regardless, there's no argument that in 2042 it's orders of magnitude easier to run servo motors that it has ever been, not to mention that there are all sorts of COTS camera options to use as a basis for a solid video tap In fairness, there are some parts that are going to be harder to source in the modern world, like a ground glass, but overall I think it's doable. And the idea that a small shop can build this stuff is not just theoretical. Just off the top of my head I can think of several people like Doug Fries (Fries Engineering), Jeff Williamson (WilCam), Marty Mueller (MSM) and Bruce McNaughton (Aranda Film) who built really solid cameras with a small organization. But, the thing is, Doug, Jeff, Marty and Bruce had something that was critical – customers that were willing to pay to have a camera built. As Tyler and Aapo note, that's what is missing in 2024. It's possible have an original camera built to the exact specs you want – that's how MovieCam got started – but there are vanishingly few clients who are going to pay mid-5 figures for a new film camera when there's so much solid and familiar equipment on the used market. That's always been the real reason we're unlikely to ever see a new camera for anything but the most niche applications, Like IMAX where there is just no other option, or super 8 where the stakes are low enough for the hipster market to support the project.

Back in the 80's Fries Engineering did reflex Mitchell conversions and one of the options was a version using a pellicle beamsplitter. They were popular in certain parts of the VFX community because, unlike the spinning mirror conversions, the beamsplitter option preserved the original focal plane shutter, and didn't leak light when used for things like time-lapse or animation. They did result in a loss of a 2/3-stop of exposure, and even though the pellicle was very thin, you could still occasionally see hints of a vertically doubled image on contrasty subjects. We learned to live with this since it was mostly a viewfinder thing caused by light reflecting from both surfaces of the pellicle, and didn't really affect the transmitted photographic image, but it did really freak out the occasional DP who had never experienced it before. Those Fries cameras were set up so that the mirror and ground glass was a unit that slid in to a cavity in the side of camera in front of the focal plane shutter, and they usually came with a set of mirror options - a 33% pellicle, a full 100% solid mirror for composing and previewing, and a full transmission block with no mirror. I did motion control work in the 90's with these cameras and it was common to treat them like old rackovers. You would program and preview with the 100% mirror ( because video taps sucked back in the day ) then swap to the full-transmission block for shooting ( you didn't shoot with the pellicle to avoid losing even more light when you already have 4 second exposures ). I personally never got bitten, but I know of more than one day-long shot that was lost because someone forgot to swap out the 100% mirror and shot 50 feet of blank film instead of some dramatic miniature.

Here in the States one of the go-to suppliers for small timing belts is Stock Drive Products in New Jersey. They stock small gear and belt drive components in a truly dazzling array of sizes, both imperial and metric sdp-si.com Your belt is almost certainly a standard product. The trick is always figuring out exactly which of the roughly ten million standards it is.

Looks like the rebuild turned out quite nicely

I think this is the same Fries Ultra65 that Richard Bennett down at Cinemagear talked about restoring in his blog last year. https://cinemagear.com/blog/tag/imax/ I think there were only three made, this one is s/n 003. I think that Arnie Peterson did the electronics upgrade.

OK, not exactly answering the question, but as long as we're talking about detuned lenses, I've got to mention a project I did recently where we were looking for an “olde school” look and I ended up making a cine lens out of a LensBaby. For those not familiar, LensBaby is a manufacturer that specializes in effects type lenses for the still photography market. They have a product called the Composer, which is a ball pivot swing/shift body that accepts different plug-in lens modules. One of the modules is the “Sweet 35”, a 35mm lens with a simple 4-element design, not that different that what you might have run into in the 1900's, albeit with better quality glass but (purposely) less correction. The composer housing itself is floppy, kind of toylike and completely unsuited for film production, but the Sweet 35 module is a cool lens. So I took one of these lenses, a helical focus tube designed for still macro photography, and some bits of lens mount I had laying around, locked myself in a machine shop, and Frankensteined an actual working cine lens out of it. It turned out pretty cool! It looked genuinely old, but organically “vintage” old, not “we laid on some digital effects” old. It was sharp enough in the center, but had some natural barrel and lost sharpness and picked up coma and lots of highlight bokeh as you got into the corners. The sweet 35 is an 8-perf lens, so if you're only using the center it looks pretty natural. Like I said, vintage. I regret that I don't have any pictures to post, because it was a cool project, but it's not yet released.

Does anybody know where Red used to get their lenses? The large stop motion company that I work for is circling around the idea of upgrading our lens fleet for upcoming projects. Our needs are not really that weird, but still specific enough that we end up remounting or even rehousing much of our glass, and, it's a pain. The number of lenses we're thinking of buying is large enough that we may be justified at looking at some semi-custom options, so I'm gathering names of vendors to talk to. Anybody have any leads?

Stephen, I think we need some more information here to figure out what you're after. There are (basically) three kinds of lens adapters. The first one is purely mechanical, a short tube with a flange on either end, meant to mount a lens with a deep flange (backfocus) depth to a camera with a shallow flange depth. It simply holds the lens in place at the correct distance from the film plane and fills up the space in between. These adapters do not have any optics in them, and, if made accurately, allow the lens to focus to infinity. They are commonly found adapting a still lens to a small-format cine camera. They don't affect the size of the image at the focal plane or the image brightness, though you may see a "crop factor" because you're on a smaller sensor, and what was once a normal lens on your 35mm still camera now crops down to a mid-telephoto in super 16. The second type is mechanically like the first, but with active optics in the tube. This type can shift the focal plane around or shrink/grow the image. For example, I have a PL-to-EF adapter that goes on a cine zoom and expands the academy-sized image to cover a full-frame sensor, at the expense of creating an image one stop dimmer (because it's spreading the same light over a larger area). There are "speed increasers" that go the other way, shrinking a full-frame image down to an APS-C or 4/3 frame size. Since they take the image and concentrate the same light over a smaller area, the image gets brighter, but there is no crop factor (because the image is smaller). The third type is exclusively a play for macro focus. These are usually purely mechanical, like type 1, but they purposely have way more than the "correct" amount of back-focus, usually by 10-50mm or so. By spacing the lens out farther than normal they basically extend the focusing threads allow additional close focus, but at the expense of no longer being able to reach infinity (because the lens can't get back far enough any more). Think of them like old-school extension tubes on a still camera. Sometimes these macro tubes can employ a second helicoid to make them adjustable and thus more versatile. This type of tube definitely will affect your image brightness. Effectively, you're moving the focal plane farther from the lens, and the inverse-square law will start to come into play. The effective focal length will also seem to grow as you focus closer. These are both results of the basic laws of optics, but since they are exponential you usually only notice them in macro work (many true macro lenses have barrel markings to indicate this shift, btw). Look up "bellows factor" from still photography for a better explanation. In your case you probably have two normal "type 1" adapters. The first goes from the 66mm backfocus of a Hasselblad lens down to the 46mm backfocus of an M42 camera body, and the second goes from the 46mm backfocus of an M42 standard lens down to the 40mm backfocus of the Aaton mount. Assuming there's no glass in there, and you can focus to infinity, your exposures should not shift (though your Hassleblad still lens will be marked in F-stops instead of T-stops, so you might want to dial in an extra half stop or so)

Well, don't forget that anamorphic lenses actually have two focal lengths, one in the horizontal axis and one in the vertical axis. The mumps effect and bokeh smearing and general weirdness that you sometimes see when there's a strong focus pull is largely the result of one lens trying to be a 35 in the horizontal plane and a 70 in the vertical plane.

This is interesting. If you've been to NAB in the last decade it's been clear that Nikon has been trying to get themselves a little of the video-side action like Canon. About 5 years ago they bought the VFX motion control company Mark Roberts. They didn't really explain why, and it seemed an odd fit. But then I saw the two companies had a combined NAB booth that showcased their joint foray into remote-operated camera heads for high-end sports and automated camera pedestals for smaller news broadcasts, all featuring tight integration with Nikon DSLR's instead of the more typical video cameras you might expect. It made sense, Mark Roberts needed funding to explore markets other than the slowly evaporating film VFX world and Nikon really had to find a way to grow their photo division out of their limited (mostly) still camera market. Canon always had first mover advantage since they already had a toehold in broadcast and film with their lenses, and their consumer and prosumer video products going back to the 80's gave them a product line to build on. But Nikon has never really had that. Yeah, they build microscopes and sport optics, but on the photographic side... they're mostly a still camera company. Now that everybody with a phone - which is to say pretty much everybody - already carries a pretty good camera in their pocket all day long, I've got to believe that the niche for dedicated still cameras is getting pretty dang tight, at least by historical standards. Nikon kind of has to do something, it can't let Canon keep gobbling up market sectors.

Well, you mentioned 'alleyway' and 'extant lighting' Maybe the lighting was some type of discharge lighting or LED's and was strobing at the power supply frequency. That's not uncommon in the lamps used in 'high efficiency' area-type security lighting. If you were in a place with a 60Hz supply, that would mean that you had a 60 or, more likely, a 120Hz strobe, which is a nice multiple of a 24, 30 or 60 FPS frame rate. A 60 Hz strobe should be noticable, but a 120Hz strobe might not be visible to the human eye. But to a camera that exposes each frame for a few millliseconds, it would make a difference. If you were shooting with a narrow enough shutter angle (like you went up to 1600 ASA, and the camera compensated exposure by reducing the exposure time) you could find your exposure time getting smaller than one light cycle time and your image sampling falling in and out of phase with the lighting. Sometimes you might start recording and find yourself exposing in phase with the lights while they were on, sometimes you would start recording and this time you were out of phase and exposing when the lights were off.

How about Ken Stone up in Fraiser Park? http://stonecinema.com/

How about this series of JIS screws at McMaster-Carr https://www.mcmaster.com/catalog/129/3396/94387A514 They're JIS standard, which means the heads are a bit thinner and less wide than the typical metric series (1.3 x 3.5mm versus 1.7 x 4.0mm) I use them for installing Nikon and Canon lens mounts on the specialty optics we build at work. In 2x6mm they're about $4.71/50

What he said, the fotodiox part. Really, a damn good adapter for $43. https://fotodioxpro.com/products/ab-c-p?_pos=4&_fid=c1012711a&_ss=c

I remember "And God Spoke" from 1993 In theory a comic mocumentary about the making a big Biblical epic, but in practice actually a documentary of every real film I've ever worked on.

The best option is probably an unconverted Mitchell GC or standard. They're not even a little bit sexy, but they're inexpensive, readily available, and have rock-solid registration if they've been even minimally maintained. Their focal-plane shutters offer really good light sealing, so they are useful for time-lapse or animation, and they won't become a leaky mess when you stop them and they have to sit for a moment while you calculate out how far you want to backwind. They are almost purely mechanical, but there have been a variety of motors produced by 3rd party companies for everything from stop-motion to high speed. Most of these cameras use an external spring-belt for mag drive. This can be switched from the takeup side to the supply side to run backward. the Standard model (with phenolic gears) is good to at least 36fps, while a GC (with metal gears) will run all day at 120fps if you keep the movement oiled. Both cameras will happily run in reverse at 24 fps. We used to use these cameras all the time for motion control work, an often ran the film back and forth several times to build up exposure layers, like, on a spaceship where you might have one hero "sunlit" exposure, then turn the key lights off, backwind the film, and re-expose a long exposure to burn in the portholes.

Supposedly, every Mitchell 35 ever made had an 8:1 shaft with an accessible D-spline that could be hand cranked. I know for a fact that this is the case with the Fries Standard conversion sitting on sticks in the corner of my living room, and that was one of the last Mitchells off the line, built in 1974. Don't know about their 65-5perf line, but from what I can recall those were mostly just upscaled NC's. I have personally never hand-cranked a camera, but was once told by an olde-timer that you should mentally hum the "Addams Family" tune to keep time.

You shouldn't have to compensate anything. The maker made it so that the shutter is open for .75 seconds. The prism will take 1/3rd of the light, leaving 2/3rds of the light through to the film, so your effective exposure time as seen by the film is 0.75sec * 2/3 = 0.5 seconds. 1/2 second, conveniently, is an easy number to work with photographically, and probably why the builder chose that weird .75 sec mechanical shutter time in the first place. So treat your Bolex as if it is a still camera with a fixed 1/2 second exposure time. Set you meter to sill mode, dial in 1/2 second exposure, and adjust your aperture and ND accordingly. All this assumes that your lenses so not have iris rings marked to pre-compensate for the prism loss (Bolexes are not my specialty, so maybe someone can chime in) if the lenses are marked to take the prism into account, then set your meter to the speed between 1/2 sec and 1 sec, which is technically .707s but may be listed as .7 or 3/4, either way it's close enough to make no difference. they key thing is that your movie camera is now a still camera with a fixed exposure time, and you have to calculate aperture and ND as if you're taking stills

Also, I would note that sometimes there are auxiliary cameras attached to the main camera. I used to do a lot of VFX and it was common for a movie with extensive facial replacement to rig two small witness cameras out a few feet on either side of the film camera, converged a couple of yards in front of the lens. These would be recorded and provided to the VFX people to help them understand what the actor was doing in the Z axis.

It's not attached to the main camera, it's in the hands of a set photographer, crouched in the lower center of the frame. You can see her(?) right hand supporting it. Feature films often employ a separate still photographer to generate all the publicity materials, and sometimes they photograph right along side the regular film crew. Though it's not as much as an issue today, in the days of film you wouldn't want to use a still taken from the motion picture camera - you'd have to cut (or at least dupe) the camera negative, and a 4-perf frame is tiny for a still. This photo is from 2007, so the camera is likely a DSLR, either film or digital, and so it makes noise when it shoots. Hence the photographer has enclosed it in a blimp, which is why it looks so big an boxy.

There was a bit of a scandal in the still photography world back in the 90's about the performance of the medium-format Zeiss lenses. One of the medium-format camera companies (I think Bronica) was looking to sell more of their cameras, and their research showed that the biggest issue stopping advanced amateurs from moving up to medium format was the cost of a set of lenses. At the time, Bronica, like Hasselblad and Rollei, all used the same exact lenses, all made by Zeiss but sold in different mounts by each manufacturer. So Bronica contracted with a Japanese manufacturer (Tokina, I think) to build a line of "budget" lenses. But the thing is that Zeiss had been cruising for years on legacy designs, some of which dated to the 50's. And while I love that beautiful Hassleblad glass, the decades without competition left Zeiss with a design refresh cycle that was... well, let's just call it a less than enthusiastic Tokina, on the other hand, started with a clean sheet of paper and the latest optical technology available in the 90s. Buyers soon noticed that the "budget" lenses were noticeably sharper and contrastier than the (much) more expensive Zeiss-built "professional" lenses.