I am very new to SLR picture taking. I have a Nikon D60 with the 18-55mm lens. I am a very active saltwater fish/coral aquarist. I want to learn how to take pictures of corals in great detail. I would appreciate any suggestions for a lens. I have it in my head that I need a macro lens to get in as far as I want. Also, I need a tripod. Know where I can get one?? Thanks for any advice peeps!