Who is working with 23.976fps Projects?

[Dick the Flick]

I wonder how many of us are involved with 23.976 fps projects?

 

My reason for the question is that the MTC standard of 23.976 fps doesn't exist? (ie when MIDI spec was developed this more recent standard didn't exist and hasn't ever been integrated)

 

MTC is apparently squirted out of Logic at 24 fps when you choose 23.976 as your frame rate. So if you ever attempt to sync anything externally using 23.976 MTC, there will always be sync discrepancies. MTC can only be encoded as 24, 25, 29.97, or 30fps. However, neither ProTools nor Logic offer up any objection either when transmitting or receiving MTC when the frame rate of the project is 23.976.

 

Please could anyone who has or is working with this standard drop a note to say what the circumstances are that they do this? (Even if simply running a movie internally in Logic)

 

I work in the UK and have been involved in films that have been shot in the USA and involve CGI that then end up in sound post in Europe ....... hence the reason for my 23.976 fps picture work using Logic. However I prefer to sync the QT movie on an external machine (I use a Canopus Box and Virtual VTR software) ..... which causes sync nightmares.

 

I'M SIMPLY CURIOUS AS TO UNDER WHAT CIRCUMSTANCES AND HOW COMMON THIS FPS RATE IS USED?

 

All the very best

D-t-F

P.S Many thanks to Ski for his knowledge in this field.

[ski]

Hi D-t-F,

 

Thanks for the props!

 

Pretty much every project I've worked on for the past 5 years has been 23.976 fps. Picture streams off of a dedicated video drive, and I display it on the second of two 27" monitors. Sync is never an issue, and I can't say that I've ever experienced any apparent hit in processing power by running Logic + picture from the same computer.

 

Part of the reason this may be the case is that I always request DV work prints. They decode very quickly, and are my codec of choice for work prints. Another codec I was recently turned on to is 422 Pro Res Proxy. Picture looks great and seems to decode just as fast as DV, the difference being smaller file size. However, if your work prints are encoded with h.264, even on a powerful computer you will likely experience a significant processing hit; this is because the data is so highly compressed that it takes gobs of processing power to decode.

 

So perhaps one solution for you would be to request work prints with your specification of codec (suggesting again either DV or 422 pro res proxy), the idea being that you could run those movies from your computer directly without worry of taxing your processors.

[Dick the Flick]

Absolutely spot on Sir S! I also use PAL DV (or NTSC if from your neck of the woods) and agree about the load being very onerous if using H264 or some such like.

 

That's fascinating that you run 23.976 the whole time

 

I guess I'm still living in the dark ages then with this idea that the Mac needs every ounce of power. I do however severely pound the poor thing .... often running 5.1 mixes and 256 track counts with audio "bounce in track in place" to cope with stuff like Hollywood Strings on PLAY and also much 5.1 stuff recorded with real orchestra / choir + all sorts of nutty stuff (ie real musicians!) Am I wrong to worry about protecting the poor DAW from running alongside a movie too?!

[ski]

Hi Dick,

 

I'd suggest just trying it out, running video directly from your computer and onto one of your monitors (preferably streaming it from a dedicated drive, but you could try it off of your system or project drive as a test). See how it runs. Might be just fine!

 

If it's not, then I'd suggest the approach of running larger libraries (like Hollywood Strings) from a separate slave computer rather than video from a slave. My thinking is this: not having to give picture sync a second thought is priceless, but there's no foolproof way to achieve perfect picture sync on a slave via MTC when running 23.976 movies. However, there is a foolproof way to slave processor-intensive libraries from a slave computer.

[Dick the Flick]

Thanks Ski

 

You're absolutely right in that it represents a fool proof way of working in sync. What I've done for the past few years is usually run picture and music in sync for no more than around 3 or 4 minutes at a time. Within those chunks there's a long enough time to check everything's working ok ...... it's simply the difficulty of screening a section more than 6 or 7 minutes when you get unstuck by more than a couple of frames that things start to look noticeably wobbly when you're screening for a director. I usually make some excuse and press stop / start like a nervous tick! So far no one found me out but it's a bit pants really!

 

Meanwhile I'M REALLY INTERESTED TO HEAR HOW MANY GUYS IN EUROPE USE 23.976 FPS ... WHAT REASON'S ANYONE ELSE USING 23.976 ... there must be more of us?

 

I'm out of the studio from now until Monday but will experiment.