I've recently been pondering shooting everything at 1080i60 and just slowing it all down 16.7% to 1080i50 for PAL markets. That gives an 83.3% slow-mo, which would be pretty nice, especially for pelagics. Loads of stuff I see on TV is slightly slow-mo.
What do you all think?
not sure about your particular NLE but, Final Cut particularly advises only stepping the speed down in fractional increments - i.e from 100% going slower, one should only try 75%, 50%, 25, 12.5% etc...... they state that the frame blending that goes on will then only have to judge the same "gap" in between frames...
I've totally disobeyed this point in some edits and not noticed a difference - maybe the subjects were never moving fast enough to freak out the frame blending(?).....
Regards slo-mo, in general.... all my shots come out at least 75% with most coming out at 50% - if the subject isn't moving too fast then the frame blending "engine" in the background does a great job of keeping everything smooth, crisp and sharp.... it's a personal preference thing as it really exaggerates the effect of projecting this dreamy, floaty world in which we are diving....
(plus - as a final note - when shooting the Daily Dive DVDs it makes even the most uncoordinated of flappy-armed Open Water diver look kinda more like the James Bond stunt double that they wish to look like in said vids.... 
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