Advice on underwater camera case

[neuroanatomist]

I also scuba dive, but I haven't been for a few years (since before having kids). That means my underwater photography predates my dSLR years... But I've shot film underwater. The biggest issue is often lack of light - determine how much you're willing to push the ISO up, you may need that at the deeper end of the snorkeling range (I often get down to 25-30' when snorkeling).

As a side note, this is one area where I think the G1 X is a great choice - you're getting nearly an APS-C size sensor and the much better ISO performance that brings, and that camera with the dedicated Canon housing is $1100, compared to several hundred more for a good dSLR housing with the appropriate lens port(s), not including the camera. The new little Sony with the 1" sensor would also be a great underwater camera, in a package the size of the S100. But, I digress...

As for the Underwater scene mode, I'd skip it - the scene modes are JPG only, and I'd recommend shooting RAW to maximize your ability to post-process the images (and push the exposure a little further if needed). However, there's an underwater white balance setting which you can use, and that WB will be stored in the RAW metadata when you pull up the file in your converter.

Here's one specifically for your camera, it's a little pricey though, this one is probably overkill, but it looks nice.

I agree about getting the full housing, not a soft bag. The Canon one is rated to diving depth (130'). Actually, the Canon housings are pretty reasonably priced, as housings go - the Ikelite one for the S100 costs $100 more.

Have a great trip, and let's see some pics from it when you get back!

Here's one I took in Belize a few years ago, snorkeling off Caye Ambergris (I also dove the Blue Hole when I was there ) The subject seems appropriate for me...