Patrick Neary

I shot a low budget feature for a two producers who told me about their previous DP who didn't use a meter at all on their first film. I was wowed, they were aghast, and that's (one reason at least) why they didn't hire him again.

Nope. (thanks for the try though!) Light transmission from a lens is not affected in any way by the size of the surface where it's image is landing. I think this whole thing might be just an issue of poor ad copy, rather than any interesting video/optical phenomenon.

I owned a very nice 16bl, and really liked it, but the few CP-16s I've used were much quieter. And I loved the 1.85 markings on the groundglass! (of the CP)

also I should note for anyone who didn't catch it in the other thread, I did send a note to the company asking specifically what causes the light loss, the reply was: "Hi open up the film stop...1 or 2 stops. Thanks"

Hello all- there has been an ongoing discussion here about this PL adaptor ring: http://www.xl1solutions.com/ADAPTERS.htm the big mystery seems to be why (as they claim) there is a 1 to 2 stop loss of light-when obviously this is just a bare naked, hollow, metal ring.

Hello again Laurent! yes, a lens' brightness or transmission doesn't change, no matter where you mount it. Looking more carefully at the pdf I mentioned earlier, it seems issues of video lens design are more about correcting chromatic abberations than light transmission, so that was a purely bizarre tangent of mine. I was working toward a guess at what the company's rationale is with their claim of a 2 stop light loss with that adaptor...I'm beginning to think it's something they just pulled out of their shorts. Or there's a very simple explanation, and I'm going to feel like an idiot- Perhaps it's time to post this question as it's own thread to see if anyone here knows either why there would be a light loss, or if in fact there would be a light loss with just a simple metal adaptor ring. this is starting to feel unhealthy!

...so i did write to the company, asking what causes the 1-2 stop light loss. the answer: "Hi open up the film stop...1 or 2 stops. Thanks" Ok then, mystery solved!

thanks for the clarification, Sam- As further proof that I am officially spending way too much time on this- Here's something I found at: http://www.theiabm.org/pdffiles/canonoptics.pdf (a very informative primer on video optics from Shigeru Oshima from Canon) chew on this: (2) F-number To maintain the same brightness, the smaller the image size of the lens is then the smaller (brighter) its Fnumber needs to be. In other words, the F-number should be proportional to the image size. In a television camera the number of raster lines is the same regardless of the image size, so reducing the image size reduces the area of the pixel (the diameter of the electron beam). The amount of light received by the pixel therefore decreases as the image size decreases. This decrease hasto be compensated for by reducing the F-number in the same proportion. A film camera is different; the same F-number can be used with any image size. The pixel on film is the grain of silver chloride, the diameter of which is the same for all film sizes. As the image size is reduced, however, resolving power is lost, even though the F-number is not affected. If I'm reading this right, then reducing the imager size DOES require compensation in terms of light. But is this, as David mentioned, simply a matter of the camera being rated at a lower "ASA", or are lenses designed specifically for certain video cameras (and their optical blocks) endowed with F-stop scales that relate only to those specific cameras? My head hurts. That pdf is fabulous reading though, I heartily recommend it!

could very well be, I mean there were only like 9 cuts in the entire film, weren't there? I wonder if there are still a couple editors out there who won't give up their clackity old moviolas?

Crushed like a bug!!! :) (I couldn't find "embarrassed face") So the claimed 1-2 stop light loss for this thing is still anyone's guess...At some point one of us is going to have to just write the company and ask what's up with that?

Very nice! Thank you for taking the time to post these, I wonder if this forum had a section just for illustrated shot/lighting dissection, if more shooters would post this kind of thing. It's so informative to see how others approach lighting issues and problems!

The flange focal distance for a PL mount camera (this is from specs for the Arri 35BL series) is 51.97 -51.98mm. One reason for this depth is to clear the mirror shutter of the camera. I don't know the flange focal depth of a Canon XL-1, but it's clearly much less than 51.97mm, so to acheive proper focus with a PL mount lens on that camera, you need to move it away from the camera body 51.97mm minus Canon's specified flange focal depth. If you peer deep into the lens mount of any Arri, you'll see it's quite cavernous compared to what you see looking into the XL-1's mount. As for the prism block, I know at least in professional cameras, like a digibeta, the prism block is rated at a stop, usually around 1.4. I'm no expert on CCD prism blocks, but I assume this means that the prism block arrangement is robbing a certain amount of light coming through the lens. My guess is that if the lens hasn't factored this into the design, then your lens stops (even T stops) will not correspond to the actual amount of light hitting the imaging chips. Somebody here must know more about the details of prism block characteristics than me, hopefully they can confirm my guesses or crush them like a little bug!

It's a mystery to me! The photo of the product on their website clearly shows just a simple metal adaptor ring, no optics. Again, maybe the prism block robs some light? I'd love to hear their rationale for the light loss. :blink:

Why am I reminded of that classic Onion headline: FACTUAL ERROR FOUND ON INTERNET! Anyway, back to Ryan's question, American Cinematographer had a cool little article a while back about Fox's "24" shooting their background plates (for either front or rear projection) using PD-150s and dvcam. It seems that you'd be very safe using HD! The list of 35mm films that used 65mm for effects work is a long one, the issue being one of image degradation in the days when effects were an optical/photochemical affair rather than a digital one.

...a quick look at a magnification table shows that a 1 stop (1 and 1/5 to be exact) loss occurs at 1:2, while you have a 2 stop loss at 1:1.

Bell and Howell made a high-speed-only version of their filmo, i think around 120fps.

yes, but pulling a lens even several millimeters further from the film plane will turn it into a macro, and i mean MACRO-only lens. You wouldn't be able to focus further than several inches away. To begin to start losing stops just from extending the lens, you need to be working at 1:1 magnifications or greater, if I'm remembering correctly. could the 1-2 stop loss be from factoring in the Xl-1s prism block?...seems odd!

"What they mean about the focal length being increased by two is because the pulling of the lens is longer since the lens is further from the pickup device than the film plane should be from the same pl lens. This is also why there is a loss of light." If this were true, you wouldn't be able to focus the lens anymore, or it would essentially become a macro-only lens (think extension tubes). Unless this device does have some optical element built it (it sure doesn't look like it), then forget what i just said!

If I understand the product in question- it looks just like a metal adaptor ring, no optics. A 27mm lens will have the DOF of a 27mm lens. An 85mm lens will have the DOF of an 85mm lens.

hi again- shooting only a stop over won't blow out anything, it will just give you a richer negative- you would have to overexpose over three stops to start making a real difference, but then, you could also just shoot clean and have the magical telecine person give you a great, contrasty blown out look. (thanks, jonathan!)

oh absolutely- despite the technical, er-shortcomings- of Neil Young's Greendale, there were shots in there that just looked like an incredible impressionist painting. I'd love to know what his post-route was, going from 18fps super-8 to 35mm print! Also, I thought I read somewhere (uh, oh, another "factual error" found on the internet!) that Jim Jarmusch's "Coffee and Cigarettes" had at least portions shot on super-8, and that whole film looked fabulous. Maybe somebody knows with more certainty about that one... I have done super8 (transferred up at Flying Spot) that did look very nice, even 16mm-ish, but I was referring more to a situation where a client (especially a media-savvy one) is expecting REALLY clean 16mm or 35mm or Digibeta type look, and gets super-8, there's going to be hell to pay...

Hi- I'm very fond of Tiffen's chocolate filters for that sort of thing there's a frame grab on my hopelessly out-of-date website from a short i shot up at Vasquez Rocks where we used a very light chocolate (i think #1 or 2) to give the sort of effect you might be talking about...it's at www.maxfilm.net in the "still frames" page, part way down, the guy in the orange jump suit.

Hey! Nice to see SOMETHING is being shot around here! Here's a dumb, question, is this a day or night shoot? because if it's day at the gates I usually pass through at PDX, there are enormous windows everywhere flooding the place with daylight.... If I were doing a small shoot there I'd use available daylight and bring along a couple small 400w jokers or 2' kinos for cleanup. No worries about blown fuses. have a good shoot!

yay! it's finally on dvd- I can finally toss out this tattered VHS version- All "making of' pieces should be this good!

There was a run of "cutting edge" super-8 commercials more than a few years ago, Nike specifically, along with a bunch of others. The notion that super-8 is a superior imaging medium just because it's film doesn't really fly. It's a special effect, something you use for a distinctive look, not as a general-purpose production medium. I can't imagine shooting anything that is supposed to say "quality" on jumpy, grainy, dirty super-8.