50fps varispeed v 50fps project speed

[Simon N]

Quite a simple question really. Is there any difference between setting your project speed framerate to 50fps as opposed to leaving your framerate at 25fps and changing the varispeed setting to 50fps?

Thanks

[Stuart English]

If you leave your project frame rate (TIME BASE) at 25 fps and shoot Varispeed at 50 fps, on playback the clip will play at 25 fps i.e a 2:1 slow down.

If you shoot at a project frame rate (TIME BASE) of 50 fps, on playback the clip will play at 50 fps.

[Simon N]

So is there any difference in the quality of the final image acquired using either flavour? i.e. is the data laid down in the same way and is it just with playback that the variances occur?

[Cail Young]

is the data laid down in the same way and is it just with playback that the variances occur?

The images are recorded identically. The only differences are:

With a 50P project rate you can record sound.
50P will give you real time of day timecode (it uses the field flag on a 25fps TC track to denote alternate frames) whereas 50fps on 25P will run at twice real time.

[Florian Stadler]

If you change the base framerate within a project you will have trouble in post.

[ericyoung]

If you then log and transfer the 50fps clip recorded with a 50fps timebase into a FCP 25p timeline. will it play with the 2:1 slow motion at 25fps?

[Anders Holck]

If you then log and transfer the 50fps clip recorded with a 50fps timebase into a FCP 25p timeline. will it play with the 2:1 slow motion at 25fps?

No, it will drop every second frame, effectively giving you 25 fps at 90° angle (If shot at 50 fps, 180°)
You need to conform it to 25 fps using cinematools and then it will play back in 25 fps 1:2 slow motion in fcp, and will include audio at 50% pitch.

Regards
Anders

[ericyoung]

No, it will drop every second frame, effectively giving you 25 fps at 90° angle (If shot at 50 fps, 180°)
You need to conform it to 25 fps using cinematools and then it will play back in 25 fps 1:2 slow motion in fcp, and will include audio at 50% pitch.

Regards
Anders

Thanks Anders. That's an interesting workflow to enable audio for slow motion!

[Simon N]

So in essence, frame for frame the images are identical? Negating sound there is no reason to choose one over another save playback issues?

[Cail Young]

So in essence, frame for frame the images are identical? Negating sound there is no reason to choose one over another save playback issues?

Yes.