Hi everyone! I was trying to record 60fps footage on a Lumix GH5s for the first time, but as far as I can see in both QuickTime and Premiere Pro, the footage is practically 30fps - i.e., every two adjacent frames are identical. I'm not sure what went wrong?? Or is it a footage interpretation issue?
Setting I used on GH5s:
Rec Format: MP4 (LPCM)
Rec Quality: 4K 8bit 150M 60p
In QuickTime (Mac):
Inspector window says "FPS: 59.94";
When I advance the video frame by frame, every two adjacent frames are identical.
In Adobe Premiere Pro 2018 (Mac), imported full-res not using proxy:
Properties window says "Frame rate: 59.94";
When I go through the footage frame by frame, every two adjacent frames are identical;
If I "Interpret Footage" as 29.97fps, it plays slo-mo but stuttering, i.e., every two adjacent frames are still identical.
So bottomline, the camera seems to have recorded 30 unique frames per second (each frame twice), instead of 60 unique frames per second.
I ran into this exact same problem today. Took me hours to figure out that it was a simple slip-up on my part.
I'm guessing you've discovered the answer yourself by now, given it's been months since you posted your question, but I wanted to reply with my own solution anyway, just in case someone else comes along wondering why the duplicate frames.
For me, the problem was simply that I forgot to change my shutter speed. I left it at 1/50 when I switched from filming in 23.976fps to 59.94fps. By using a shutter speed that was slower than the frame rate, the camera had no choice but to default to capturing in a frame rate of 30 (the best it could manage at that shutter speed), but still played back at 60 (hence, the duplicate frames). As soon as I changed the shutter to 1/125, the problem was fixed.
A tiny little overlooked detail that had me scratching my head for hours....