Synching 35mm with XD footage??

Vanessa Whyte · July 28, 2010

Hi.

Does anyone know if there is a clever setting on the Sony EX3 Camera that will help to match the frame speed from a 35mm camera running at 24 fps?

This is for shooting an extra camera for sequence mainly shot on 35mm. The extra camera is a Sony EX3 and needs to be in sync with the other cameras for the edit. We can jam a timecode into the EX3 but I'm worried about the framerate... In PAL (for UK), the settings are either 1080/50i or 108025p. You can get to 24p if you go into NTSC settings, but is this really 24 or is it 23.98? And then do we have a problem of PAL and NTSC mixing??

Many thanks if anyone has any tips...

Adrian Sierkowski · July 28, 2010

XD's 24P is 23.98, and PAL/NTSC mixing never works out quite right. If oyu're @25 on your camera, shoot @25 on your XD, if you're @24 (23.98) then the XD @ 24 will work fine (also being 23.98).

Now, whether they'll mix well is a whole other issue....

Vanessa Whyte · July 28, 2010

Thanks for your response Adrian. So, just to clarify, you think that if I run the 35mm at 24fps it will be ok to sync with the XD footage at 1080/24p (even though it's not 24 but 23.98)? And then we have this NTSC problem in that the PAL settings don't run at 24, only 25. However, as this XD footage is mainly for VFX use to add an extra camera in the sequence and not cinema projection, I think we might be ok to mix PAL and NTSC??

Adrian Sierkowski · July 28, 2010

If you'r camera, film, is shooting 24, it's really 23.98-- so long as it's a crystal camera and that's what you set it as. As such the XD will be fine. If you're in PAL land, though, just shoot both the film camera and the XD @ 25.

Vanessa Whyte · July 28, 2010

Unfortunately, we can't do that either and the film cameras will definitely be at 24fps... Will let you know if we find a solution!!

John Sprung · July 28, 2010

How long will your takes be? If your film is at 24.000 and your video is at 23.976, 1000 frames of video will equal exactly 1001 frames of film. If you slip sync by half a frame at the beginning, you can go 1000 frames and only be half a frame out the other way at the end. That's 41 seconds and 16 frames. So, a labor intensive no cash out of pocket solution would be to just hand fit the sound.

Another solution would be to record sound for the film at 60.00 Hz time code, and for the video at 59.97. Or, you could re-clock the sound in post, which might cost less than renting two sound recorders. But you'd only need two if you had to run both cameras on the same take.

-- J.S.

Vanessa Whyte · July 29, 2010

Hi John.

Thanks for your message. I'm not sure I'm making the problem clear. It's not the sound that is the concern but the exact synching between 35mm and XD footage. The VFX work will need to make sure that these two cameras will be at the exact same frame, and the 35mm camera will definitely be shot at 24fps. The problem we also have is that jamming a PAL timecode into the EX3 gives a 25fps timecode which won't sync up with the 35mm cameras, and ideally, the VFX team want to work at NTSC anyway. So, the EX3 could be shot at 1080/24p (NTSC), and the 35mm cameras at 24fps, but then the PAL timecode will be off, and we have a mix between PAL/NTSC... Is that at all clear? I feel like I'm confusing myself!

John Sprung · July 29, 2010

So your problem is to synchronise picture with picture. I'm not sure why you'd need to do that. Do you need the shutter openings and closings exactly lined up? We used to do that for rear screen projection, but that was in the 1930's - 1960's. It was done with Mitchell BNC's and selsyn motors. If you can find a rear projection setup, you could use that, but you'd have two film cameras, not the EX-3.

Give us a broader view, what is it you want to see on the screen when this is all done?

-- J.S.

Vanessa Whyte · July 31, 2010

The reason is to provide VFX with another 'witness' camera (these are the EX3s) from a different angle to the main film camera, so that they can see another perspective from which to work from. I think the best solution is to either to mix the NTSC and PAL footage in the edit (which is only used for VFX and not for the final cinema projection), and just sync them up using the clap at the beginning of the take (in the edit) rather than bothering with synching the timecodes.

Many thanks for your help.