I think you need to decide what kind of videocam (Hi8, digital?), and then definitely check out what kind of housings are available. Do you want to be able to do stills as well? Do you want to operate the camera with the LCD open or closed? If closed, do you want/need to add on a back so that you don't have to peek into a tiny, tiny hole to see what the camera is capturing? Do you want to be able to have a long-life battery, and how long are the tapes? DV format? How do you edit them? Is your computer compatible or are you just going to "go for it" and not edit, add music, pare down so that your video tells a story ... and how do you charge those batteries? How much do they weigh (both the batteries and the charger? How can you schlep all the gear -- will you need a new bag to do so?
I recently got the Sony DCR-PC110 with a Gates Housing, which I love as it is very easy to use and I was pleased with it the very first dive (although the strobe fell off on the very first dive I used it, luckily recovered by the DM who dove in immediately and followed it down 50' with me right in his bubbles). I think their site is
www.gateshousings.com. I use the camera above and below water and it is wonderful, lightweight and I'm pleased. I also did about a year's worth of research and went to various shows to see the equipment (both cameras and housings).
Any questions? Contact me and I'll answer what I can. As I said, I've only recently gotten the camera and used it on about 6 dives thus far -- all in lovely, warm Caribbean and Florida waters.
Regards,
Margaret