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cameronfielding
03-23-2005, 09:20 PM
dont wanna sound like a noob here but something about animation production has always confused me and maybe you guys know how this works ...

How does animation compensate for difference in frames per second ?

i.e; between dvd ntsc 30fps, and the same feature at 24fps theatre release ? and even the difference between pal 25fps dvd and ntsc 30fps dvd ?

what I mean is... what speed do the animators do their work at ? -- I understand there must be a process that converts to the different formats -- but surely the big studios would not allow for say 'dropping frames ' to go from 30 to 24 fps when animation is so carefully crafted ? or the slowing down of timing when going the other way ?? and how does the sound tie in will all this ?

i dont get it ... lol

bblackbourn
03-24-2005, 01:15 AM
the short answer is - it varies.

the animated projects I've worked on have been 24, 25 & 30fps.

the key questions are
1) what is your primary distribution format?
2) are the artists used to working at one specific speed?

1)
as you say...
film: 24fps
PAL: 25 fps
NTSC: 30fps

Any conversions to other speeds will be done via the normal methods (3:2 pulldown etc)
BTW it doesn't change the "timing" - the elapsed time between 2 poses (in milliseconds for example) is basically the same on any of the formats, it's just how many "inbetweens" (interpolated if need be) are shown in that time.


2) If you have mainly traditional artists that insist on working at 24fps (they have their sense of timing - ie how many frames to place between poses - based around that), you may consider working at that framerate during production then converting to your required framerate at the end...(don't laugh - I've seen it done several times!) Used to be commonly done for traditional anim PAL projects especially as the "difference in feel" between 24 & 25 fps is virtually un-noticeable.

Sound is not affected by this per se, as it is the picture frames per second that are being changed - remember, the "timing" stays the same.

cheers,
Brad

maop
03-24-2005, 06:54 AM
Well, actually sound does change a bit if you already have everything in place at, say, 24fps, and you want to re-render your movie at 30fps. You can correct this very easily in premiere re adjusting the sound -25%

If you do it from 30fps to 24fps you need to adjust it +20%

Even when converting from 24fps to 25fps, if you just change the frame rate, sound will seem a bit high pitch (remember the chipmunks :). Therefore, you must adjust sound separately (around 4% both ways)

Then again, there might be a specific piece of software that could compensate these changes automatically, but I do it the traditional way :)

Regarding visuals, doing your animation at 24fps will save you lots render time, and since people are used to watching most movies at that frame rate, quality won't suffer much. At least in my experience.

Cheers!

Maop

cameronfielding
03-24-2005, 03:13 PM
so im working on a short at home that i intend to animate at 30fps --- ( as an ntsc dvd is probably going to be the primary distribution format )

but if for example I am required to submit on an VHS ( 25fps ) --- am I not going to lose quality in my animation because certain poses will be dropped to compensate for the new speed ? and wont this result in a slighty 'choppy' appearance on the whole ?

I am not too happy about the idea of time stretching audio in premiere ( although i have not tried this before ) -- surely the difference between 30fps and 25 would result in some distortion ? ( at the least with regards to a clearly noticable change in pitch )

what do you suggest ? --- am i thinking about all this in the wrong way ?

fwtep
03-24-2005, 04:46 PM
Well, actually sound does change a bit if you already have everything in place at, say, 24fps, and you want to re-render your movie at 30fps. You can correct this very easily in premiere re adjusting the sound -25%

If you do it from 30fps to 24fps you need to adjust it +20%

Even when converting from 24fps to 25fps, if you just change the frame rate, sound will seem a bit high pitch (remember the chipmunks :). Therefore, you must adjust sound separately (around 4% both ways)

Then again, there might be a specific piece of software that could compensate these changes automatically, but I do it the traditional way :)

Regarding visuals, doing your animation at 24fps will save you lots render time, and since people are used to watching most movies at that frame rate, quality won't suffer much. At least in my experience.No, sound doesn't change when doing a conversion after-the-fact, like when a 24fps movie is put onto video in PAL or NTSC. It only changes if you change the speed by speeding up the movie (like from 24 to 30) or slowing it down, but that's not how it's done. In other words, when you see something at 30i NTSC that was shot at 24, they haven't just speeded up the film, they've added pulldown (added frames) to compensate for the frame difference. And done properly, a 2 hour movie is still a 2 hour movie no matter what the display format.

HOWEVER, sometimes things that are shot at 24 *ARE* sped up to 25 for PAL, rather than interpolating frames. From my understanding, though I've never been involved in a project that's done that, they don't adjust the pitch of the sound because it's such a minor change (certainly not like the Chipmunks).

Fred

wireFrame
03-25-2005, 02:36 PM
Yup, no change in audio speed when you change formats unless you playback a different format from where you're working on.

Meaning: If you have an NTSC(30fps) video and you change it to film(24fps) the audio should stay the same unless you playback the 24fps on the ntsc format then there should be some audio adjustments.

The correct way to to lay-in audio is to go to the proper working format after you changed frame rate. That is if you change, say, from NTSC to Film you adjust your project settings to film format then lay in the audio (which stays the same rate) and you should have a normal audio playback (no adjustments).

Audio rate is not measured in fps but in frequency (khz, mhz). So you adjust you audio settings when you change format settings.

Lastly, the best working format is 24p or 24fps progressive. This format can easily be converted to NTSC and PAL though the addition of video pulldowns.

cameronfielding
03-25-2005, 02:43 PM
so im working on a short at home that i intend to animate at 30fps --- ( as an ntsc dvd is probably going to be the primary distribution format )

but if for example I am required to submit on an VHS ( 25fps ) --- am I not going to lose quality in my animation because certain poses will be dropped to compensate for the new speed ? and wont this result in a slighty 'choppy' appearance on the whole ?

I am not too happy about the idea of time stretching audio in premiere ( although i have not tried this before ) -- surely the difference between 30fps and 25 would result in some distortion ? ( at the least with regards to a clearly noticable change in pitch )

what do you suggest ? --- am i thinking about all this in the wrong way ?


sorry for repeating myself ... but any advice specifically about this would be great.

wireFrame
03-25-2005, 03:50 PM
I'm afraid your question was already answered but not in a staightforward manner though.

Yes, you'll lose some frames in your 30fps to 25fps conversion if you don't use professional equipments (and softwares). Your vhs version would be jerky.

24 fps (film) is the safest framerate since it be easily converted to NTSC and PAL by introducing pulldown. 2:3 for NTSC and 24:1 for PAL. I haven't done this using desktop machines though 'coz most conversions were done using not so affordable machines.

I suggest you animate in a 24p mode i.e. 24 fps film format with custom resolution set to 720x486 resolution.

You should be in a "middle ground" format (which is 24p) to cater both ntsc and pal output. Don't start on ntsc to avoid headaches later on.

maop
04-20-2005, 12:20 AM
I'm afraid your question was already answered but not in a staightforward manner though.

Yes, you'll lose some frames in your 30fps to 25fps conversion if you don't use professional equipments (and softwares). Your vhs version would be jerky.

24 fps (film) is the safest framerate since it be easily converted to NTSC and PAL by introducing pulldown. 2:3 for NTSC and 24:1 for PAL. I haven't done this using desktop machines though 'coz most conversions were done using not so affordable machines.

I suggest you animate in a 24p mode i.e. 24 fps film format with custom resolution set to 720x486 resolution.

You should be in a "middle ground" format (which is 24p) to cater both ntsc and pal output. Don't start on ntsc to avoid headaches later on.

I agree, it is better to change from 24 to 30 or 25fps (a good conversion program does some fame averaging for inserted frames), than to do it otherwise, since you would have worked and rendered extra frames that will never be used.

Cheers!

MAOP

cameronfielding
04-20-2005, 02:07 PM
thanks everyone. much clearer now.

FabioMSilva
04-20-2005, 06:24 PM
also, dont forget slow motion scenes are better filmed at 60fps.

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