Hello,
I have the A570IS with an Ikelite housing and a YS-27 strobe. It's a very good camera and the manual settings make things much easier. I'll keep it short and sweet for you. I recommend looking at the YS-27 strobe. I think I got mine for $350 new on ebay so it's in your price range. It's a slave strobe (as would any that you would use with your camera). Basically attach the fiber optic cable that comes with the strobe to your housing in front of your camera's flash (I can send you pictures of how I attached mine). The housing should have come with a flash blocker. You put that in front of your camera flash so only your strobe fires. Using your camera flash will tend to lead to backscatter (you can use the diffuser that came with your housing but it can only do so much)
Anyway, I have found that when using the strobe, use manual mode and set it for a shutter speed of 1/60th of a second and never mess with it. Then set your Fstop to 8.0. Turn your strobe up to full strength and fire. You want to have your subject typically within 6' of your camera or any strobe you get will do no good. If you want to get something farther in the distance (I did some cave diving in the spring and wanted to shoot some stalactites about 15' away) you can lower the F stop to a lower number. You won't get color, but things will turn out nicely. Just remember, always keep the subject as close as possible.
The other nice thing about using Fstop 8.0 is that your focal length (forgive me if my teminology is wrong) is the most forgiving. Basically with Fstop 8, anything from 2' to infinity feet away tends to be in focus (I've taken pictures in pitch dark caves and had almost everything come out clear). However with a low Fstop your focal range is much narrower and less forgiving. Not an issue if you're shooting things 20' away (set the focus for infinity) but anything less than 10' away you better be pretty darn close.
Also, never use the zoom on the camera, swim closer to the subject to make best use of the strobe.
Anyway, I could go on and on. I was thinking about writing an article on what I've learned using the camera so you may see that eventually. As for the underwater mode, no I don't use it. The strobe takes care of the colors. I think UW mode is more for if you use the tiny flash the camera tries to correct for a lot of the blue you'll see.
I'll link you to a few pictures I've taken using the camera rig I have. Any picture I have of a cave opening is use set to auto mode and strobe off (camera flash off). Again, I think you'll be pleased with the results. If you have any more questions I'd be glad to try to help anyway I can!
Vortex Springs:
Jim Leemhuis's Photos - Vortex Springs | Facebook
Cenote Taj Mahal:
Jim Leemhuis's Photos - Cenote Dive #6: Taj Mahal | Facebook
Cenote Chikin Ha:
Jim Leemhuis's Photos - Cenote Dive #5: Chikin Ha | Facebook
Cenote Chac Mool:
Jim Leemhuis's Photos - Cenote Dive #4: Chac Mool | Facebook
Cenote Kukulkahn:
Jim Leemhuis's Photos - Cenote Dive #3: Kukulkan | Facebook
Hope this helps!
Jim
Total newbie underwater photographer here......
I bought an A570IS along with the Canon housing for a trip down to the Bahamas next month. I'm curious about the "underwater" setting - does everyone recommend that I use that being that this will be my first try at uw photography?
I've also set aside approx. $400 for a strobe - after researching, the 2 that seem to fall into my price range are the Ikelite AF-35 and the Sea&Sea YS-17. Any suggestions? 3 More questions on the stobe:
1. Do I turn off the cameras internal flash?
2. Is there a reason (other than the obvious) that I should use a left-handed vs. right handed? Didn't know that since the cameras' internal flash is on the left if that makes a difference.
3. I see alot of people on SBoard have taken some great pictures without a strobe. Do I really need it?
Any help would be very much appreciated - thanks!