Arnie, thanks. I use a Nikon 105mm f/2.8 lens. When photographing corals, I manually focus the lens -- if you're not taking top downs with a photobox you need to be sure that you're shooting directly though the glass. 90-degree angles will be your friend. Here are some other settings (or ranges) where I usually shoot: Mode: M (Manual) ISO: 320-800 Aperature: f/7.1-18 (sharpest around 9-12, in my experience) Shutter Speed: greater than 1/40 sec (ideally in the 1/100-1/160 range and will increase ISO to get there if there's not enough light). Anything less, and I usually get a blurred image even with Vibration reduction on the lens. Most important: take a lot of pictures with different settings to see what works best for your set-up! I post-process using Adobe Lightroom. Hope that helps. Feel free to ask any other questions and I'll try to answer them.