Now and again, I shoot video of myself doing this or that. Mostly, it's playing the guitar, silat, and now and then, some sleight-of-hand.
Video is a great feedback tool. Do something, then a minute later, look at what you did, and in slomo if you want. What feels one way might look another, and it's instructional to see it and compare what it felt like with what it looks like from other there. Or in the case of the guitar, what it sounded like. (Always sounds better from the inside looking out ...)
Today I set up my little camera to record myself doing djurus, and found out three things I didn't expect. 1) The camera's AVI function shuts off at three minutes. 2) If you don't set the tripod on a level surface, you seem as if you are listing slightly to port or starboard as you turn, and it looks weird when you know you aren't. 3) I tend to do the djurus a lot faster and harder than I realized. Probably why my teacher keeps telling me to slow down.
The AVI limit I can get around by virtue of going halfway through the djurus, stopping, turning the recording off and starting a new on from the same move. It will record to the limit of the flashmem card, a couple of gigs, but not all in a single file. So there's a bit of a break in the recording at the end of Djuru #8 when I stopped to restart the recording. (And again at #14 when my dog bumped into the tripod and knocked it askew. But since this isn't a recording going out, it doesn't matter. I cut out the jostle, though in retrospect it might have been more interesting to leave it in: "Jude! Watch where you are going, you big horse!"
Can't fix the slight tilt, but I know it's there, so I can mentally adjust for it. And I can slow down the moves hereafter, though I confess they didn't seem all that fast when I was doing them.
Good to have a way to see all this.