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#1 Martin MacDonald

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Posted 24 July 2009 - 07:21 PM

Hi,

To begin with, I'm very new to S8 - i have only recently shot my first can of film on a Canon 518 SV and am awaiting it's return to see if it worked!

My question here is regarding frame rate. I've seen a few comments floating around the net saying that if you want to sync to audio, go with 24fps. Can anyone explain why that would be? To me, a higher frame rate would imply a smoother picture, but I don't understand the connection this has to audio.

Luckily for my first project i am not syncing to audio - it's effectively a silent short with a song stuck over the top that has only very abstract relation to the visual content. AND, i'm not after a high quality image, in fact the more flicker and graininess the better. Is there any reason for me to shoot at 24fps in this case, or is that just wasting film?

I really appreciate any advice or opinions on this. The more research i do the more excited i am about really sinking my teeth into filming on S8.

Thanks,
Martin
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#2 Paul Bruening

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Posted 24 July 2009 - 07:26 PM

Projectors run at 24 fps. So, the camera runs at 24 fps if you want the footage to look normal. It has been that way for so long that that's where it was standardized when sound came along. It is inconvenient for TV since the conversion to video makes for some peculiar math to make it all fit together.
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#3 Rick Palidwor

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Posted 24 July 2009 - 07:56 PM

Projectors run at 24 fps. So, the camera runs at 24 fps if you want the footage to look normal. It has been that way for so long that that's where it was standardized when sound came along. It is inconvenient for TV since the conversion to video makes for some peculiar math to make it all fit together.


Actually most projectors also run at 18fps - in fact 18 was the "normal" rate for super 8 and many cameras (and projectors) only run at 18. The reason you don't want to shoot 18fps for sound work is that most transfer set-ups ramp up the speed to 20 fps (18 fps to video flickers) and therefore sound will be immediately out of sync with picture and get progressively further out of sync over time.

Having said all that, I have argued many times that this issue is over-blown as most production sound is not usable and needs to be replaced with ADR and foley, so even if camera take is perfect sync poorly done ADR and foley will undo that. In a digital editing environment it's relatively easy to tweak the sound into reasonable sync, to act as a better refrence, making 18 sound doable.

Having said THAT, 24 is still recommended as the production track will produce a better reference to for the replacement sound.

Having said THAT, who knows if those AA batteries are running that camera at true and consistent 24fps? Crystal sync motors are recommended for "proper" film-sound work.

Having said THAT, we shot our super 8 feature Sleep Always at 18fps (and replaced all the sound later) and though I think I would opt for 24fps next time as it turned out our main camera when set to 18 was running close to 20 fps so production sound was relatively synced

Rick
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#4 Kent Kumpula

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Posted 25 July 2009 - 01:59 AM

The reason you don't want to shoot 18fps for sound work is that most transfer set-ups ramp up the speed to 20 fps (18 fps to video flickers) and therefore sound will be immediately out of sync with picture and get progressively further out of sync over time.


That just isn´t true, not if he gets a proper telecine transfer anyway. Any serious transfer house will give him a frameaccurate transfer, then the speed can be adjusted to whatever framerate without loosing synch.

Just make sure you get a frameaccurate transfer without any pulldown, then you can adjust the playback speed in post to match whatever speed the camera was running at. I´d recommend shooting 24fps for smoother movements though.
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#5 Gareth Blackstock

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Posted 25 July 2009 - 02:15 AM

Concerning the benefits of 18fps versus 24fps:
18fps is great for shooting non-synch film, lasts longer! but do not pan sideways too quickly, or film passing vehicles, it comes out "patchy" but for most moderate action i believe 18fps is fine.

24fps is ideal for all fast action, either filming a scene of high activity or running with the camera. Some state that shooting at 24fps lends a sharper image, as the film moves past the shutter faster, but i think this depends more on your camera's shutter angle, a canon 518 is 185 degrees which seems a happy medium between 220 degrees for low light, and 150 degrees for lots of light.

Shooting 24fps when attempting to synch to sound is always best.

And i think all this depends on whether you live in a NTSC or PAL country, shooting at 24fps in the states, the lab you transfer with will do so at 29fps, shooting 24fps in Australia for example, the transfer will be almost on par with what you shoot.

ask your local transfer house.....

cheers.

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#6 Steve Daniels

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Posted 25 July 2009 - 03:19 PM

I've always been curious about shooting 18 fps and then getting it transferred to mini dv, ntsc video, which of course is 29.976fps. Does anyone know what happens exactly? Does the the super 8 shot at 18fps is "re sampled" to fill the ntsc video frame rate? When played back, are you seeing 18fps playback, or some bastardized 30fps look?
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#7 Chris Keth

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Posted 25 July 2009 - 03:39 PM

Having said all that, I have argued many times that this issue is over-blown as most production sound is not usable and needs to be replaced with ADR and foley, so even if camera take is perfect sync poorly done ADR and foley will undo that. In a digital editing environment it's relatively easy to tweak the sound into reasonable sync, to act as a better refrence, making 18 sound doable.


If that is true, you have a sound man to go fire.
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#8 Rick Palidwor

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Posted 25 July 2009 - 03:57 PM

If that is true, you have a sound man to go fire.


I respectfully disagree. Even the best sound crews with best gear don't get a lot of usable production sound. Often impossible to have mic at same proximity in all shots, impossible to isolate different sounds when shooting (e.g. footsteps contaminating dialogue) not to mention camera noise (especially a problem with super 8). All the sound effects you hear in a professional movie were created after shooting was complete, and much of the dialogue. If you were a professional actor and you wrapped shooting on a project today, your contract would have you booked for Additional Dialogue Recording in a few months time. Par for the course unless you want sub-standard sound in which case your movie is dead in the water.

Rick
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#9 Martin MacDonald

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Posted 25 July 2009 - 07:26 PM

I respectfully disagree. Even the best sound crews with best gear don't get a lot of usable production sound. Often impossible to have mic at same proximity in all shots, impossible to isolate different sounds when shooting (e.g. footsteps contaminating dialogue) not to mention camera noise (especially a problem with super 8). All the sound effects you hear in a professional movie were created after shooting was complete, and much of the dialogue. If you were a professional actor and you wrapped shooting on a project today, your contract would have you booked for Additional Dialogue Recording in a few months time. Par for the course unless you want sub-standard sound in which case your movie is dead in the water.

Rick


I always wondered about how they get rid of the director yelling things during a take :P

Thanks all for the great answers here. I do live in Australia, so yes the 24fps makes sense PAL wise, although what I'm going to shoot will not likely make it further than YouTube, which from memory converts to NTSC frame rate anyway, does it not?
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#10 Gareth Blackstock

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Posted 29 July 2009 - 06:25 AM

I've always been curious about shooting 18 fps and then getting it transferred to mini dv, ntsc video, which of course is 29.976fps. Does anyone know what happens exactly? Does the the super 8 shot at 18fps is "re sampled" to fill the ntsc video frame rate? When played back, are you seeing 18fps playback, or some bastardized 30fps look?



from what i have picked up here and there, if the footage is shot at 18fps, and the finished product is to be 29fps, a frame is copied and replicated to stretch out the frame rate. Ie if you shot a flower for 2seconds at 18fps, then 11 frames would be copied and replicated to bring it up to 29fps. I am unsure of the effects of this, and others might have more accurate information on how the system works?

but, apparently most non-synch super8 cameras fluctuate in frame rate, often around 21fps to 23fps. This depends on so many variables from battery charge to camera make as to be an unreliable assumption.

good luck,
cheers
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#11 Steve Daniels

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Posted 31 July 2009 - 09:26 AM

from what i have picked up here and there, if the footage is shot at 18fps, and the finished product is to be 29fps, a frame is copied and replicated to stretch out the frame rate. Ie if you shot a flower for 2seconds at 18fps, then 11 frames would be copied and replicated to bring it up to 29fps. I am unsure of the effects of this, and others might have more accurate information on how the system works?

but, apparently most non-synch super8 cameras fluctuate in frame rate, often around 21fps to 23fps. This depends on so many variables from battery charge to camera make as to be an unreliable assumption.

good luck,
cheers


Thanks for the info. I wonder if this then takes away from that true, classic 18fps-ish flicker when watching on video. I'll have to compare projected stuff to my mini dv tape transfers.
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