24FPS vs 25FPS

Hello all.

I'm shooting a feature towards the end of the year. It's reasonably low budget, and we'll be shooting on a few different formats, but mainly it will be about 80% Super 16 and the rest various SD video formats.

I have suggested to the production that we should think about shooting 25 FPS and TK ( here PAL land) rather than 24 FPS shoot with a 25 FPS TK, because it seems to me that it will just make everything easier through the post production pathways, especially as we are planning to do a HDCAM SR DI.

I have done this several times on short films and it seems that there are far fewer EDL type problems and less grief generally after the film is photographed.

Now I know that in cinema's the film will play 4% slower and the audio will be pitched down a little compared to the video edit which will presumably be at 25 FPS. I understand it's usually easy to pitch correct the audio to take care of the sound problems. I have also heard that there is a lot of variation with the actual playback speed in most cinemas anyway...

Am I making a mistake in any of my assumptions? The main potential downfall to me seems to be that the actual timing of the editing will be slightly different in the cinema.

Does anyone think this will impact in a meaningful way on the edit? Is it different to cut at 24 FPS than 25 FPS? I know that MOST edit suites actually cut and replay at 25 FPS here in PAL land except for the light-works or a specific model of AVID?? Film Composer ?

Or should I be a traditionalist and just shoot at 24 FPS ?

Interested to hear

John Brawley
Cinematographer
Sydney Australia
+61417 087 564
www.johnbrawley.com

John Brawley wrote:

>>The main potential downfall to me seems to be that the actual timing of >>the editing will be slightly different in the cinema.
>>Does anyone think this will impact in a meaningful way on the edit ?

Well, I do. But that doesn't mean anything. The only opinion that counts here is that of your director, editor, and producer. For your end, you should also be aware that all of the action will be slowed down, so if you want to do any overcranks or undercranks, you either do or do not need to compensate, depending on your own perception.

Personally, I'm of the opinion that the originating format should match the distribution format, especially in terms of frame rate. But maybe that's just me.

Mike Most
Chief Technologist
Cineworks Digital Studios
Miami, Fl.

John Brawley wrote:

>>I understand it's usually easy to pitch correct the audio to take care of >>the sound problems.

In my experience - which can't be considered extensive circa 2006 by simple virtue of the fact that there is more pitch shifting sw out there than I've had time to try - for critical work it can be better to pitch scale tracks individually; with a formant based pitch shifter * settings that work well on voices might not be the best for string instruments, etc.

*I prefer to say "pitch scaling" as you're pitch shifting within a fixed time base if the 4% change is done as anticipating the projector's speed difference.

Sam Wells
film/.../nj

Hi there John

The old discussion of 24 v 25 has been going on for years. In Australia and other 50Hz countries, projectors usually run at about 24.7 fps so really the whole thing is a bit semantic.

The problem is to 24 or to 25.

Using 24@25 is a fudgemental pain in the bum.

It is still worth considering what we are doing in Dr. Plonk. The film is TC'd at 24fps directly to HDD via eSATA (450 MBps) at 1920x1080 444 RGB 12Bit. The files are stored on IDE drives, bladed and batch exported once onto an eSATA RAID as self contained movie at cutting resolution, say DVCPRO-HD 24fps and also back to the source IDE as a reference file. You now have 2 identical files.

Cut the project and when complete, create a new timeline at 1920x1080. Copy the cutting timeline and paste into the new one. From here, you reconnect the media back to the source IDE.

Export this 1920x1080 12Bit RGB as an 2K image sequence and send it off for grading.

Call me some time

Jon Armstrong
http://www.nildesperandum.tv
61 8 8332 9467
0428 500 240

Jon Armstrong wrote:

>>It is still worth considering what we are doing in Dr. Plonk. The film is >>TC'd at 24fps directly to HDD via eSATA (450 MBps) at 1920x1080 444 >>RGB 12Bit.

There is no such thing as telecine to a 12 bit format. There is no such thing as a 12 bit 4:4:4 RGB format. Telecine is, by definition, a real time process to a video format. 4:4:4 dual link RGB video is, by definition, 10 bits. The only place 12 bit linear exists is inside the telecine, and this is not available for recording because there is no defined specification for it.

People seem to throw around terms like "12 bit" with great ease these days. The problem is, it doesn't exist, at least not in the video world.

Mike Most
Chief Technologist
Cineworks Digital Studios
Miami, Fl.

My apologies, I was not thinking. yes 10Bit

Ain't it a shame that everything goes back to what works on television. Gee I hate it.

Jon Armstrong
Colonial idiot

Jon Armstrong wrote:

>>Ain’t it a shame that everything goes back to what works on television. >>Gee I hate it.

Well, that's not very different from saying "ain't it a shame that everything goes back to what's technically feasible and economically affordable." We'd probably all be driving electric cars that do 0-60 in 5 seconds and use no fossil fuel by now if someone could have found a way to build them affordably. With unlimited funds and unlimited time you can do pretty much anything, but the point is to come up with ways of doing things that are practical and possible.

"The world is a business, Mr. Beale. It has been since man crawled out of the slime."

Mike Most
Chief Technologist
Cineworks Digital Studios
Miami, Fl.

Michael Most wrote :

>>We'd probably all be driving electric cars that do 0-60 in 5
>>seconds and use no fossil fuel by now if someone could have found a >>way to build them affordably.

The reason we don't have (the choice of) electric cars (yet) has little to do with technological or economic feasibility. And yes, I know this comment is off-topic and doesn't belong here.

Greg Lowry
President
Scopica Inc. / Scopica3D
Vancouver

Michael Most wrote :

>>Well, I do. But that doesn't mean anything.
>>Personally, I'm of the opinion that the originating format should match >>the distribution format, especially in terms of frame rate. But maybe >>that's just me.

Well it means something to me !

It seems that there are some good reasons to shoot 24 FPS, indeed when our primary release format will be 24 FPS. I just naively thought it would be easier to go 25 FPS.

Thanks all for the advice..

John Brawley
Cinematographer
Sydney Australia
+61417 087 564
www.johnbrawley.com