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50Hz 30Fps 16mm Safe Shutter

Published : 6th February 2008

I will be shooting some night time scenes in Paris (50Hz) on 16mm which will be used for flash animation so needs to be at 30Fps. My calculator tells me the safe shutter angle, considering I will be shooting public buildings lit by discharge lamps, should be 108°, the SR3 has fixed angles of: 90°, 135°, 144°, 172.8° and 180°. I doubt if I will have the opportunity to test before. Any suggestions much appreciated.

Roger Simonsz
DP/Operator
Angled in Paris


33.333 fps at any angle, 25.000fps at 180 deg and 24.000 at 172.8 deg are the closest that you can get (at least according) to pCine, which has never let me down.

According to the math, your best bet might be to choose one of those options and re-speed the footage in post. 33.333 fps is 11% faster which is less of a difference than shooting 25 fps which is 16% slower, but either way is a pretty big jump.

It would depend on whether this is MOS or sync sound and how wrong the action would look slowed down.

I would say that it is time to have a chat with the post-production folk...make it their call so you don't get yelled at later, but I am guessing that they will opt for 172.8 shutter at 24 fps to which they will apply the bog-standard 3:2 pull down...complaining all the way that we cameraman don't understand their needs and refuse to shoot what they ask for.

All the best (and with memories of a lovely meal!!!)

Mark Weingartner
LA based

No this was not mean to be sent privately...if you want to know more about the lovely meal, you just have to go to Paris and hunt Roger down yourself!


>>It would depend on whether this is MOS or sync sound and how wrong >>the action would look slowed down.

(or speeded up...I know, I know, 25 fps is slower than 30 fps)

Mark H Weingartner
LA


I've shot & AC'ed a few times at 30fps in 50Hz environment. 108° is indeed the only way out. 435 ES is the only solution (never tested 105° which is preset on 235). 24fps/172.8° is another solution even though the French don't know much about 3:2 pulldown. So do check with post before.

Leo Mac Dougall
Cameraman Paris


Thanks Mark and Léo

I found out that flash animation actually works at 31 FPS! I will propose to shoot at 33.3333 as it is the closest I can safely get, even though it will eat stock.

Mark, have you got your clown photo yet? Looking forward to the next meal, maybe in your town next time.

Roger Simonsz
DP/operator
Gastronomically in Paris


I only have rudimentary experience working with Flash, but I seem to recall that the software permits you to set any frame rate you like. This feature is vital to reduce file size for the web. I therefore don’t think that you have to shoot at 33.3 frames per second. Are you planning to scan the film, rather than transferring to video? I’m asking because in case of a video transfer you’ll always end up with 25, or 29.97 frames on tape regardless of your shooting rate.

Best:

Joerg Schodl, Cinematographer,
Los Angeles


class="style9">>>I will be shooting some night time scenes in Paris (50Hz) on 16mm >>which will be used for flash animation so needs to be at 30Fps.

Why? Does flash only play back at 30fps? I just opened Sorenson Squeeze for Flash and found all sorts of frame rates available.

I'll bet it's because the animators insist that 30fps gives them the smoothest feel for their work. If your work is just background or foreground for the animation there's no immediately obvious reason to shoot your footage at the same speed they're animating at. (I'm sure someone out there can come up with a reason and enclose it in a particularly sarcastic reply. :) )

How about shooting 24fps with a 172.8 degree shutter and adding 3/2 pulldown to get you up to 30fps? Seems a lot simpler than trying to make 30fps work under 50hz conditions. I've done that with a director who insists on shooting 24fps regardless of how many graphics are flying around. The graphics get added later at 30fps.

I hate to say it but there's a good argument for HD in this situation: shoot at 30, dial in a 50hz shutter, and other than having to deal with an electronic format that will never look as good as film you'd be in good shape. Then again... I've seen Flash compression and I think film is overkill for most of what I see out there on the web. I'd be curious to see what a Varicam at Film Rec/Dynamic Gain 500% would do with a night exterior.

Barring that, it's amazing how specifically cholera can attack animators when introduced into the right water supply. Surely there's an up-and-coming student animator who'd jump at the chance to animate at 25fps.

24fps worked okay for Disney...

-Art Adams
Director of Photography
Film | Hidef | Video

San Jose, CA, USA
www.artadams.net
415.760.5167


Thanks to all who replied to this thread a while back. We landed up shooting 24FPS 172.8° shutter 7218 and the rest worked out fine.

For those of you with a fast internet connection and too much time on their hands, you too can drive around Paris at night on:

http://www.the-passenger.com/

The driving sequence was shot on HVX by the producers if I recall, the little scenes when you've reached your targets were done on 16mm.

Have fun

Roger Simonsz
DP/Operator
Going round in circles in Paris



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