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Daniel Klockenkemper

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  1. In practice I doubt it's common at all. The vast majority of camera support devices are balanced relative to the camera's center of gravity, which puts the nodal point of the lens forward of the pan axis. Renting specialty equipment to balance the camera around the nodal point is not only an additional monetary cost, it also requires extra time to configure and re-configure when there are lens changes, etc. It might create significant extra difficulties for certain camera operating styles (e.g. handheld). When not strictly needed for VFX or technical purposes, I doubt many productions would feel the costs are justified. To what degree nodal pan and tilt movements contribute to "naturalism" in storytelling is a separate and more subjective topic. Certainly, human eyes rotate very closely to their nodal points; however, when people turn their entire heads the rotation is centered around the neck/spine, which puts the nodal points of the eyes far forward, similar to common camera supports. I also feel that most of the time, camera movements are intentionally performed in order to change the perspective, so a minor offset in parallax would be seen as a benefit rather than a drawback, if it is even considered at all.
  2. The simple answer is that they don't. For the Honda EU6500 or 7000 generators, the model number represents the possible momentary peak load. The maximum sustained load is 5500W/45.8A according to the spec sheet, but you should still allocate some some headroom for good measure. The modified generators I've seen have 50A circuit breakers on them. 60A is just the next size up for the cable/connector, which does help to ensure that the cable is less likely to be a limiting factor.
  3. This is how it's explained in the Set Lighting Technician's Handbook section on fresnels: A fresnel lens is an approximation of a single/simple plano-convex lens, and it's a bit easier to find ray diagrams of those on the internet. I attached a picture I found, from Firebird Optics' "Introduction to the Plano-Convex Lens" (https://www.firebirdoptics.com/blog/intro-to-the-plano-convex-lens), which shows how the light rays of a PCX lens don't converge evenly.
  4. As rehoused wide stills zoom lenses go, I think it'd be hard to find better mechanical quality than the Sigma or Tokina (without going to a bespoke rehousing service like TLS). If either of those lenses meets your needs, I wouldn't necessarily hold their stills origins against them. There aren't too many alternatives for sub-$10k wide cinema zooms... Duclos Lenses sells low-budget wide-angle zooms from Zunow and DZO, but I tend to think that you get what you pay for. Have you considered the Canon CN-E 15.5-47mm? On the used market they'll still stretch your budget a fair bit past the Sigma, but it's a proper cinema lens of excellent build and optical quality, and it might be the best overall value in that category. Its range would also make useful as more than just a wide variable prime like the Tokina or Sigma tend to be.
  5. This topic again... 😅 Lenses do not have crop factors. Period. The focal length of a lens is always what it says it is. It does not matter if the lens does or does not have the ability to cover a particular sensor or piece of film completely. A lens cannot become a different lens when placed in front of a different format; that would violate the laws of physics. "Crop factor" only relates to the size of one format compared to another format. The ratio between two formats is always the same, even with no lens involved. The combination: format ⋆ focal length ⇒ angle of view. Which means: If you keep the format the same and change the lens, you get a different angle of view. If you keep the lens the same and change the format, you get a different angle of view. So to get around to your question... 🙂 A S35-sensor camera might be paired with a typical set of focal lengths, such as: 16mm, 24mm, 35mm, 50mm, 85mm. To choose lenses for a full frame camera that have the same angle of view as the above set, you'd multiply by the 1.4x crop factor - the difference between the two formats - which would tell you to pick these focal lengths: 22.4mm, 33.6mm, 49mm, 70mm, 119mm. But in practice this would probably get rounded to more common numbers: 24mm, 35mm, 50mm, 75mm (or 85mm), 135mm. There are quite a few "Super 35" lenses that can cover a full frame sensor. And an excellent set of "full frame" lenses will work just fine on Super 35 formats, too. So start by determining what angles of view are needed for the particular story or style, then choose a format, and pick the lenses from there!
  6. Hi Edith, I did a fair amount of operating with the Moviecam Compact, which is quite similar to the Arricam ST, and have used the LT a bit as well. I'd agree with your assessment - neither is a mirrorless digital camera, so in the grand scheme of things they're not dissimilar. All film cameras are heavier on the shoulder, so do weight training, wear a back brace, all the usual precautions for the physical aspect. Both LT and ST will require a proper high-end tripod and head, so there's no practical difference there either. Unless it was absolutely necessary to shave every ounce for some reason, I'd probably prefer to have the ST. It's entirely possible to have a lighter ST build with a prime lens and 400ft magazine. Productions that demand the LT often end up bulding it up with 1000ft magazine, studio zoom, etc. anyway and it loses whatever advantage it had over the ST. I'd rather have the flexibility to mount the magazine on top and a little more room on the body, both inside and outside. And the ST's increased mass should help it run a little more quietly, too!
  7. On a film camera (like your example) this is a reflection off of the side of the film gate, which is usually a shiny metal. I've simply heard it called gate flare, but there could be some more official name that I don't know of. Interestingly, I've seen similar flares on mirrorless digital cameras from low-quality lens adapters that lack proper internal light traps or flocking. If there's not a broader name for it, perhaps we need one? Mechanical flaring, perhaps?
  8. I'd suppose that "EM. NO." is short for emulsion number.
  9. Through some searching, I found an old Akkuman catalog; the cells are: 3372319 Saft VHCS3200 3,2Ah NiMH Sub C. Normally I would say that cells above 3000mah should have no trouble running the camera at high speed. However, given that the pack's manufacture date is June 2005, the cells' capacity are likely much reduced at this point. I would consider having the pack re-celled. Sub-C NiMH cells can be found with capacities up to 5000mah, but higher capacity cells often also have more pronounced self discharge. When I owned an ACL, I never needed more than 12V - the motor could quickly reach 75fps with high-amp NiMH cells. I would advise against using a V-mount or lithium chemistry battery without a voltage regulator. The circuit board image you posted does look similar to a voltage regulator, with the small screw on the blue component probably being for voltage adjustment. "VCLX" is a model of block battery made by Anton Bauer that has a 14.4V 4-pin XLR output, which makes the regulator theory very likely. There are D-tap to 4-pin XLR cables on the market that could make it possible to use a V-mount with the regulated cable. You should test the cable's output with a multimeter before connecting it to the camera. I would highly recommend having a professional, or a friend who is savvy with electronics, check things out for you!
  10. The Sony cameras' eND do take a small amount of time to adjust, even at the fastest setting. I think if the iris ramp were done over the course of about 3 seconds (or longer), the eND would be able to keep up and the effect would be seamless. If the desired effect is for the depth of field to change as fast as possible, a motorized setup would likely be faster - you'd only be limited by the speed of the motors. Iris rings and dual-pola variable NDs don't have to turn very far to make exposure changes. I've used the Sony eND in a few scenarios when the exposure changes dramatically, e.g. a garage door opens and sunlight pours in, or the lights come on unexpectedly in a dark room. In the former situation, the change was gradual so the effect was seamless. In the latter, since the lights coming on was a surprise to the characters, it made narrative sense that it would take a second for their eyes to adjust, so I lived with the very brief overexposure; the auto adjustment is smooth and otherwise doesn't call attention to itself.
  11. Keslow Camera is listed as a place to rent the Cinefade, but presumably you've already checked with them. Panavision demonstrated a similar system as a prototype at Cine Gear Expo a few years ago; you could check with them, but I haven't heard any updates so I don't know if the filter was ever produced: https://www.cined.com/panavision-liquid-crystal-filter/ An alternative would be to use a Sony camera like the FS7 II or FX9, both of which have an electronic variable ND which can respond to a manual aperture change if the ND is set to auto. Those cameras are surely much more available than either filter system. For any other camera, you could also add a motor to a dual polarizer style variable ND in a geared filter tray, like the Bright Tangerine One Tray. You'd need a multi-channel MDR like a Preston system - while I haven't used a Preston this way, it should be possible. If you go this route, you'd probably also want to be careful in selecting the combination of pola filters to make sure the filters don't introduce color shifts when you change exposure.
  12. Several years ago I was looking for more information about why Zeiss might use a triangular aperture (technically a Reuleaux triangle) and came across a white paper I wish I'd saved about the effect of aperture shape on laser optics. What I recall from it is that a perfectly round aperture produces concentric rings of diffraction, radiating outward evenly in all directions; while a triangular aperture has lines of diffraction that radiate away parallel to each pair of corners, kind of like a 6-point star filter, with areas in between the lines unaffected by diffraction. So my guess is that Zeiss was trying to delay the onset of diffraction-related softness at small f-stops, to keep the image acceptably sharp for a wider range of apertures. It certainly seem characteristic for Zeiss at that time to care more about the sharpness of the in-focus parts of the image than they would about the softness of the out-of-focus areas.
  13. This is a fairly easy query to look up - there were short sequences shot as stills with the Canon 1D Mark III, which has a burst mode capable of 10fps. The different gamma from the 24fps footage is also a minor tell. https://shotonwhat.com/cameras/canon-eos-1d-mark-iii-camera This article gets the frame rate slightly wrong: https://www.reuters.com/article/uk-mumbai/slumdog-crew-took-to-the-streets-of-mumbai-idUKTRE49T37T20081030
  14. Without having data for the bulbs spectrum*, my best guess is possibly a little bit, but probably not very much. The strongest UV filter I've personally seen - a Tiffen UV-2A - has a perceptible light yellow tint, which means that it does slightly filter some blue wavelengths in the visible spectrum. If the filter appears clear/neutral to the eye, then it follows that it shouldn't affect the brightness of the bulbs' output in the human-visible spectra. To be sure, I'd recommend visiting the location with the UV filter you plan to use, and metering the bulbs through the filter. A C800 color meter might also be informative if you can get your hands on one. Of course, the only way to be really sure is to shoot a film test, but I know that's a luxury these days. The original article I remembered about UV filter transmission is here: https://www.lenstip.com/113.1-article-UV_filters_test_Introduction.html There's also this more recent one from Lensrentals: https://www.lensrentals.com/blog/2017/09/looking-at-clear-and-uv-filter-spectrograms/ * I searched a little bit for this, but the few spectral transmission graphs I could find for tanning bulbs only show the UV portion, and omit the visible light wavelengths.
  15. While I don't have any experience with tanning beds - neither from filming nor otherwise - I do know that the major filter manufacturers have and do make UV filters in 4x5.65" sizes. Tiffen has a few strengths, with older filters labeled UV haze 1 or 2, and newer filters named UV-15, UV-16, and UV-17; higher numbers filter more UV. Schneider offers a UV-410 filter that claims to cut most UV wavelengths. I haven't personally tested any of the above UV filters... I am aware of a test of stills filters, which found that B+W (owned by Schneider) was by far the most effective at actually filtering UV, while the lone review on B&H of the Schneider UV-410 filter claims that the filter added significant flare/glare. It's possible that the B&H reviewer is correct, but it's also possible that they made some mistake, like not bothering to clean the filter, or didn't mitigate it by tilting the filter... A polarizer can help with UV exposure in landscape scenarios, but this might not be applicable in your situation, with the camera aiming directly at the UV source. I'm sorry I can't help with anything more than hearsay! But at worst the UV would cause a loss of contrast, for which you might be able to compensate somewhat in the grade. Flicker would be my biggest concern, and it seems like you're already prepared for that. Your test with the Cine Check will be the most informative. In the absence of a test, I would film with a 144 degree shutter, assuming a 60Hz line frequency.
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