Need help with shooting Underwater

I'm headed to Hawaii in a few months and my mother-in-law wants to shoot with her SD870 while she snorkels.

We have the camera, getting the Canon housing, but what about the flash?

Do I need an external flash if I'll only be in like 3-10 feet of water?

And what other accessories do you think I'll need?

If you're not going more than 10 ft. down, you shouldn't need flash, at least in Hawaii. I'd just go with the housing. But you may want to disable the flash if you're not photographing something really close up. There's a diffuser for the housing, but with a subject at any distance you'll get a certain amount of backscatter from particulates in the water.

I agree with Jon. But be warned, that unless the water is perfectly clear, she's gonna get nyah pictures. See my shots with an A570IS here. No flash on any keepers. Flash just lights up the particles in the water, as Jon said..

http://kirkhmb.smugmug​.com/Travel/338559

Only the Molokini ones are decent, the rest.......

KirkHMB wrote in post #4809243
I agree with Jon. But be warned, that unless the water is perfectly clear, she's gonna get nyah pictures. See my shots with an A570IS here. No flash on any keepers. Flash just lights up the particles in the water, as Jon said..

http://kirkhmb.smugmug​.com/Travel/338559

Only the Molokini ones are decent, the rest.......

Why did those turn out the way they did? They seemed extremely flat. (no offense intended)

What did you mean by 'nyah' pictures? Or was that a mistype?

Probably because they were looking down from above, so no real chance for shadows. Try shooting horizontally so there's some chance for the light to sculpt things.

"nyah" - flat, relatively low colour. Flash will let you get colour, but flat lighting will kill any sense of depth. The shallower you (and your subject) are, the less "blue" things will look, too. The reds get filtered out first; that's where a flash can help. But unless it's close up, the light will all get reflected right back into the lens.

I always find you have to use photoshop and do a simple autolevels. Here are two of those pics with autolevels.

Thanks for the info guys!

Anything else I might need to know?

beachbum2277 wrote in post #4809399
Why did those turn out the way they did? They seemed extremely flat. (no offense intended)

What did you mean by 'nyah' pictures? Or was that a mistype?

Jon wrote in post #4809524
"nyah" - flat, relatively low colour.

Jon nailed Nyah quite well. The water wasn't crystal clear. The sun wasn't quite as high in the sky. Not a great location. Nothing you have much control over, except the location.

Molokini in the morning is fantastic, sign up for the AM trips if you go. Read the brochures, check online forums to see where the best snorkeling is on whatever islands you go to. Other places I was snorkeling had a break nearby (kids were surfing), so stirring up sediment. Others were late in the day, not as much light to work with.

I knew they were flat, so no offense taken, they were posted as a warning the MIL may not get great shots, even with a decent camera and housing.

But, they are a ton better than I ever got with a 27 shot disposable camera, or my little Minolta Weathermatic A, so I try to look at the bright side

Thanks for that. I have been reading that between 11:00 and 2:00 are the best times to go and to shoot horizontal to what I'm shooting. I guess that's about as much as I've got. The MIL has been there before and has snorkeled there a few times so I believe she knows the hot spots. I just know she's gonna blame me for the shots! haha!