Blackmagic Forum

I'm using Resolve 15 Beta Version 15.0.0B.037 and having issues slowing down footage because it looks choppy.

I have a video clip shot in 59.94 fps. My project timeline is 23.976. I right click on the media clip in the timeline and choose "Change Clip Speed". I change the speed to 40% and the playback looks choppy. I've used this method with the same measurements in Resolve 14 and it's played back very smooth. Any ideas on what I can adjust?

Try this instead:
right click on clip/Clip Attributes
Set video frame rate to 23.976

Change speed back to 100%

George Deierling wrote:Try this instead:
right click on clip/Clip Attributes
Set video frame rate to 23.976

Change speed back to 100%

Thanks for the suggestion. It's still choppy. I can't seem to figure this one out.

OK, now tell us about your machine, the format of that material and its codec.

I'm afraid we'll need more information on your hardware, driver versions, which codec the clip is in and your general workflow - all of which can impact the playback speed.

Please refer to viewtopic.php?f=21&t=69837

I was also going to ask if he sees this choppiness in the rendered 23.976 output as well as on the timeline ?

For 59.94 to 23.976 slowdown surely it's just a matter of changing the frame rate in the Clip Attributes ?

Doing it the way described......

BMDR User 9201 wrote:I have a video clip shot in 59.94 fps. My project timeline is 23.976. I right click on the media clip in the timeline and choose "Change Clip Speed". I change the speed to 40%....

....will effect slowdown, but 'Ripple Sequence' needs to be selected, otherwise the clip will be truncated (at 40% of it's length) to match the original clip duration.

Checking this through myself (in 15_b2) with a 1080/59.94p source clip, I don't see any difference in the motion characteristics of the rendered 23.976 outputs when the slowdown is effected by either method. There is no frame replication or deletion involved in either case.

I suspect also that the choppy playback BMDR_User _201 reports is a timeline performance issue.

George Deierling wrote:Try this instead:
right click on clip/Clip Attributes
Set video frame rate to 23.976

Change speed back to 100%

Don't understand the logic there. When loaded on the 23.976 timeline 'Change Clip Speed' reports the clip as 100%/23.976, so what's to be changed 'back to 100%' ?

Uli Plank wrote:OK, now tell us about your machine, the format of that material and its codec.

Shrinivas Ramani wrote:I'm afraid we'll need more information on your hardware, driver versions, which codec the clip is in and your general workflow - all of which can impact the playback speed.

Please refer to viewtopic.php?f=21&t=69837

Resolve 15 Beta Version 15.0.0B.037

Machine:
MacBook Pro Mid 2015
Processor 2.2 GHz Intel Core i7

Media clips:
MPEG-4
H.264, Linear PCM
59.940 fps 1920x1080

Workflow:
I insert the media clips (same codec and frame rate) into the Timeline by clicking and dragging the clip from the Media Pool to the Timeline. The media clips have in/out points on them.

I right click on the media clips that are now on the Timeline. Select "Change Clip Speed" and adjust the Speed to 40%. I have tried checking the box for "Ripple Sequence" and the playback is choppy both ways.

Try to convert to ProRes and see if it's still choppy. You machine might be challenged with MP4.

Uli Plank wrote:Try to convert to ProRes and see if it's still choppy. You machine might be challenged with MP4.

Thanks, I'll explore this option. For what it's worth, I've been editing MP4 without complications and have converted 59.94 to 23.976 @40% playback speed smoothly in Resolve 14.3 (same machine). This is the first time I've had to do it since using Resolve 15 Beta and discovered this issue.

Looks like BM should check this one then.