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Steve Switaj

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    Cinematographer
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    Portland OR

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  1. 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?
  2. 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)
  3. 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.
  4. 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.
  5. 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.
  6. How about Ken Stone up in Fraiser Park? http://stonecinema.com/
  7. 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
  8. 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
  9. 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.
  10. 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.
  11. 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.
  12. 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
  13. 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.
  14. 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.
  15. 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.
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