Slow Motion 50p / 60p to 25fps

ROCKMORE

ROCKMORE

Veteran
I've been shooting slow motion tests mostly at 50p because I'm in pal and slow them down 50% on a 25fps timeline in CS4. Today I shot some tests at 60p NTSC and converted them slowed to 40% on the same timeline. I removed the frame blend in all cases. Everything seem to work well.
The 50p transferred at 50% is an even number which makes sense but, the 60p to 25 is not.
The 60p to 25 may be degraded to some degree even thought it looks quite good. I suspect I may be better off sacrificing the extra 20% slower motion for sharper final result.
Anyone have a technical explanation to what extent my final 60p to 25fps image may suffer over 50p to 25fps.
Thanks
 
Just wait until you have CS5, you can then take the fotage 50 or 60p directly into Prem natively and then use Interpret footage to enter your desired actual rate ie 25 fps. There is no frame blending or conversion etc it is just playing back the frames at a different rate per second so there is zero quality loss. I have a video of it on my site at http://www.tdepost.com/videos/2010/4/13/premiere-pro-cs5-dslr-support.html here I do it with 50p footage but the result is the same for 60p, although you wil need to be aware that some lights with strobe if you shoot 60p in a PAL country
 
Evan, I have checked out your site regarding CS5.. informative, thanks. Quick question, above you mentioned frame blending in CS5. Can you now add a clip to a timeline and not have frame blending auto-on? thanks.
 
mgilbert said:
Evan, I have checked out your site regarding CS5.. informative, thanks. Quick question, above you mentioned frame blending in CS5. Can you now add a clip to a timeline and not have frame blending auto-on? thanks.
Click to expand...

Just threw some clips in and frame blending was off by default.
 
evanbutson said:
Just wait until you have CS5, you can then take the fotage 50 or 60p directly into Prem natively and then use Interpret footage to enter your desired actual rate ie 25 fps. There is no frame blending or conversion etc it is just playing back the frames at a different rate per second so there is zero quality loss. I have a video of it on my site at http://www.tdepost.com/videos/2010/4/13/premiere-pro-cs5-dslr-support.html here I do it with 50p footage but the result is the same for 60p, although you wil need to be aware that some lights with strobe if you shoot 60p in a PAL country
Click to expand...

I am looking forward to CS5.
 
ROCKMORE said:
Anyone have a technical explanation to what extent my final 60p to 25fps image may suffer over 50p to 25fps.
Click to expand...

You shouldn't be suffering anything additional even in CS4 right now.

You're not generating new intermediate frames, you're just playing back the 60fps footage at 25fps by interpreting the footage. Each 60 unique frames per second are just played back slower at the 25fps timeline; this isn't the case where you try to take footage shot at 25fps and slow it down, because you need to generate new intermediate frames by either blending, duplicating, or synthesizing in post to generate a higher fps for slow mo (ie. as if you shot a higher fps)

The "evenly divisible" only matters when you are converting 50p to 25p (i.e. selecting every 2nd frame) , not in the slow motion case by using ALL the frames - you are just playing back at a slower fps
 
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