A lot of good advice here. I will add a few more tips.
Without a flash, your photos will be a big disappointment in all likelihood. To minimize the disappointment, take photos in the top 30 feet where the sunlight is still fairly strong. Get very close to your subject, no more than 2 to 3 feet away. Anything else is going to leave you with blue photos, since the water filters out the red part of the spectrum. If your camera can be equipped with a red filter, then you can get some pretty decent photos as long as you stay shallow.
Lastly, be very careful of the reef. Pick your photo opportunities carefully, in places where you won't accidentally kick things. You would be surprised how many times novice photographers leave a trail of destruction. They just don't know what they are doing. Get your buddy to spot you, and keep you from destroying things. That's why everyone is telling you to get more experience before you grab a camera. It takes a lot of experience and control to keep from wrecking the reef when your eye is glued to a camera's viewfinder.
Without a flash, your photos will be a big disappointment in all likelihood. To minimize the disappointment, take photos in the top 30 feet where the sunlight is still fairly strong. Get very close to your subject, no more than 2 to 3 feet away. Anything else is going to leave you with blue photos, since the water filters out the red part of the spectrum. If your camera can be equipped with a red filter, then you can get some pretty decent photos as long as you stay shallow.
Lastly, be very careful of the reef. Pick your photo opportunities carefully, in places where you won't accidentally kick things. You would be surprised how many times novice photographers leave a trail of destruction. They just don't know what they are doing. Get your buddy to spot you, and keep you from destroying things. That's why everyone is telling you to get more experience before you grab a camera. It takes a lot of experience and control to keep from wrecking the reef when your eye is glued to a camera's viewfinder.