How long does the battery last and can a extra be purchased and installed between dives?
JOSEPH H I didn't pay close attention, but I think a fully charged battery lasted about 1.25 to 1.5 hours. The battery is not removable, so you can not change it between dives.
One thing to consider about this camera that I did not think about until I used it, is that, with every exhalation, the bubbles from my regulator would distort the picture and make a lot of sound. By mounting it on the side arm of my underwater still camera (instead of my mask strap), I was able to eliminate the problem. Just something to consider when comparing underwater video cameras and their mounts.
I hope this helps you with your decision.
RICHARD K battery lasted 28 min. in 55F Pacific ocean , La Jolla cove . 10 min. in 34F Lake Michigan ice dive . In the Keys or a pool you'll run out of memory before the battery dies . I've recorded whole dive/rescue pool practice ,more than an hour.
no, you can't swap batteries.
MARC K I get about 45 minutes out of a charge. The battery is sealed into the Camera so all you can do is recharge it. Hope this helps. By the way it takes wonderful video.