The forward thinking minds of hollywood are pushing towards 48fps and even 60fps, and I anticipate this day with glee!
I do too... I think... but the advance screening of the Hobbit at 48fps got a lot of criticism for looking like a TV live broadcast/ too much like video etc.. There is certainly something special about 24fps when it comes to fictional storytelling. Seems like it's much more difficult to lose yourself in a fantasy story when the framerate (and res) get really high. It makes me wonder whether they might be better to simply dump alternate frames of the Hobbit. I bet the thought has crossed their minds. But I suppose the shutter angle might then be too small. I wonder what shutter angle their 48fps is shot at... Maybe they're using 360 degrees now, rather than the customary 180 degrees of 24fps footage (anyone know?), in which case it would seem to be an option.
So it seems to me that you would want to stick with one frame rate, if you wanted to mix footage
Not wanting to answer for Drew, but... ABSOLUTELY! Mixed framerates are a PITA and to be avoided if possible.
That brings up another topic. Since the Canon can shoot at 1920x1080 or the 720p, where do most of you stand on this setting? I have always shot it using 1920 but have friends who prefer the 720 mode.
Steve
1080p all the way for me, as someone who is shooting to build an archive of footage for future use. If the camera can do 60p at 720, and only 30p at 1080, I might use 720-60p for the occasional project specifically for slow motion. But I would still want to be building my general archive in 1080p. It's simply more resolution/information. Having said that, I still downsample my 1440x1080i HDV footage to 720p for YouTube delivery, rather than do the slight horizontal upscale to 1920x1080. I do that mainly for smooth playability on the widest number of systems. If I was shooting one-off videos and dumping the footage after, rather than archive it, I might well choose 720p.
As for the framerate, I'd go with 30p over 24p in general for underwater footage. Again it's simply more information, and more flexible in post-production for various delivery scenarios. And as blaise says, you can easily slow down 30p by 20% to 24p, which really suits a lot of underwater shots. I really want to shoot 1080-60p as my general format in the foreseeable future (unless 4k becomes mainstream really fast), and I'm hoping that becomes more commonplace in projected stills/video cameras such as the Panasonic GH3 and Canon 70D, without having to invest in a FS700/RED etc.. Having said all that, Howard Hall shoots his stock at 4k-24p, or at least he was a couple of years ago, so who knows... Maybe 5k-120fps is the only way forward... 