Best way to get slow motion for 1080/24P film?
 

Do you think it would be better to capture 720p60 and adjust the resolution, or to get 1080i60 and interpolate the 24P frames? The first option is a lot simpler, but I am not sure which one would yield the best results.

The best way would be to shoot 1080/30p and adjust the frame rate of the clip. That'll give you full-resolution frame-accurate 1080 slow motion; it just won't be very slow is all.

Other than that, I haven't spent any time trying it but I'd guess you'd have more success with 720/60p rather than de-interlaced 1080/60i.

Try a test both ways. Also try shooting 720 24pN at 60 fps
and uprez that to 1080 24p....

I doubt I will have the luxury to test this shot, so I wanted to bank on your experience.

Try testing ahead of time.....
Go outside and record some traffic or
a scene similiar to what you
will be recording....
I have been doing this 25 years
and I still test and experiment
all the time.

Re
 

Barry, sorry for the newbie question, how you can adjust the frame rate of the clip?

just do it in NLE but setting the speed of clip, i think he ment it this way...

If you try to slow down too much in NLE (at least in FCP) you'll get ghosting as inbetween frames are "rendered." But maybe if you shoot 1080/60, you can then drop it in a 30fps timeline and get slowmo.

I've beend oing lots of slow-mo using 720p, 60fps/24p and it's come out beautifully, plus I can slow it down even more in post without worrying about the ghosting. I've gotten a 10 second shot up to a minute long without seeing the ghost renders, and that was with birds in flight. However, their wings move pretty fast, so if you don't need to catch such a fast moving object, you'll be fine doing it in post.

Shake it up
 

If you're on a Mac the best way is to use Shake to create your slow-motion effects. Unlike FCP which uses frame-blending which looks like staggered frames Shake instead uses "optical flow-based retiming" to create glass-smooth slo-mo. Check out the Shake demos on the Apple site and you'll see what I mean.

If you're on a PC I'm not sure which of the post-add ons would do the same thing as Shake.

After Effects 7 for one. Realviz retimer, or revisionfx twixtor (the people that started it all).