Editing a new project — which frame rate?

[Bret Hampton]

Robert

Almost certainly your camera records 24fps at 23.976. Only certain high-end digital cameras and camcorders can record true 24. Pretty much any dvd, blu-ray, streaming, tv is either 23.976 or 29.97. So you’re not changing frame rates at all.

Just do ProRes at that frame rate, make sure you use HQ for best quality and you’ll have a much better edit experience than trying to use MP4 files which although much smaller have to be decoded to play.

[Tod Hopkins]

This should be a non-issue for you. In modern, computer based video there is generally no practical difference between “24fps” and “23.976.” You can switch one to the other without any loss. Historically 24fps is the film rate and 23.976 was the matching video rate. The difference matters a lot when you are shooting film or if you are doing complex synchronization between multiple systems. Converting from one to the other should be lossless though you will change the running time against real time slightly.

In analog days, to go from film to video meant you had to go from 24.00fps to 23.976fps, and this caused problems with synchronization. In the digital age, the difference has become almost insignificant, especially in computer based editing. It’s important to be aware, but it rarely matters.

You should, however, be consistent.

[Robert Withers]

Thanks, Bret and Todd for your thoughts. I bought this Canon because the sales guy at B&H said it does true 24fps. And that’s what Media Info says the files are. The Canon offers both options.

A friend had a weird sync issue with a mix of her 75 min film that we speculated was due to the difference, based on the numbers and FCP7.

In any case, someone suggested trying to encode 10-20 files at a time instead of 500. I’ll try that.

Thanks again for the input,

Cheers

[Robert Withers]

Bret and Todd,

Here are some discoveries related to my query.

Bret, you are SO RIGHT! I went back and used MediaInfo on different copies of my video files and they were all 23.976 fps. I then started up my Canon Vixia and went through the menus — one option is to record at 23.976 fps, which is as close as it gets to 24. This is the cheapest Canon model that doesn’t limit recording to 29.etc fps.

The anomaly I remembered was with the film of a friend who had shot in film at 24 fps, had it transferred to 24 fps progressive video but edited in FCP7 which interprets 24 as 23.976, exported .mxf files for a mix then found that the mix seemed to slip out of synch at the rate of about 1 frame per 1,000 frames so that it was out significantly at the end of the 80 minute show. We never really figured that one out for sure but the mixer fixed it and it wasn’t critical for that film.

As to your comment that it doesn’t matter because it’s modern and digital, Todd, I don’t really follow this though it may be true. Does an audio track recorded at 48k sampling rate play any differently when matched to 24 fps vs 23.97 fps? That’s over my pay grade, but I did decide that if I was cutting to fractional time rhythms I had do know whether I was counting frames at 24 fps or 30 fps. 6 frames is 4 per second and 8 frames is 3 per second. In the stuff I do that makes a difference.

The weird answer for the AME commands was this:

If I used two of 3 methods, either importing AVCHD files from a card copy into the Media Browser in AME and dragging a custom preset onto the selected files, or bringing files in the same way and doing Apply to Queue, AME would apply a standard Premiere Pro Res 23.976 preset to them all. The only way I could get AME to use my preset was to copy the AVCHD files to a desired folder using the Mac finder and then import them into the queue window by double-clicking in an empty space to import them from the finder location instead of the AME browser. That way AME used my custom preset (which was ProRes HQ 24 fps) to import them.

Thanks again for everyone’s responses.

Cheers,

Robert