that's a shame you can't change the shutter speeds. it's going to be quite difficult capturing fish unless they are slow movers or standing still (swimming still, actually.)
i'm REALLY bored right now, so i felt like illustrating a couple things for photographing fish. for slow movers, auto everything usually does a good job unless you're going for a specific effect. it's those constantly moving mid and upper level fish we all have that lend the most difficulty. i'm using my group of rasboras as the guinnea pigs (guinnea fish?)
the trick to capturing these fish is a fast shutter speed, like i mentioned before. the only problem is that the faster your shutter speed, the more lighting you'll need to get a nice picture. this is why you can capture images in relatively dark situation with a slow shutter speed. all of these photos were captured in macro mode, wide angle. i love macro! i set the zoom to wide angle because that allows me to clearly capture objects from 2" to 1.5' away, which is perfect for dealing with my aquarium.
in this first image, the shutter speed is manually set to 1/60 sec, aperature set to auto . i'm willing to guess that 1/60 is about as fast as i'll ever need to go for fish. i could have found a happy medium with 1/25 sec or so, but i'm using 1/60 for illustrationi am using a 1x55watt AHS over the 29gal which is plenty bright, but there is alot being blocked by the anacharis and hortwort that i have let grow up to and across the surface. regardless, you can see how the image is crisp, but very dim. in my opinion, this is unusable unless you're going for that effect.
in this second image, the lighting remained the same as the same picture, but the shutter speed was slowed down considerably to 1/4 sec. the lighting is improved, but the constant movement of the rasboras creates motion trails that typically undesirable, unless again you're going for that effect.
please ignore the aweful flash in this last picture. i used it merely to illustrate how well fast shutter speeds work with ample lighting. everything is clearly visible, crisp, and well colored, with the exception of the rasbora that is in the foreground.
i'm almost done with this psuedo-impromptu-tutorial. the best advice i can give you if your camera doesn't give you a lot of manual control is to take LOTS of pictures. you'll increase the chances of getting that "keeper" the more pictures you take....
