Hi Drew,
As John mentioned, the “slow motion” shooting modes offered on the Sony cameras offer a very low quality, and for short bursts only at that!
You’re not going to get the kind of super-slow-motion you see on TV, which is shot with expensive gear shooting hundreds,or even thousands of frames per second!
I see that the NX5U does offer 720p60, so that may be the best solution, and crank up the shutter speed as John mentioned to get clear stop-motion on the fast action.
If you take the resulting 60p footage and put it into a 24p sequence in Premiere, you get very nice slow-motion playback at 40% speed.
Google “creating beautiful slow motion in premiere” for a tutorial
Thanks
Jeff Pulera
Safe Harbor Computers