Sorry to hear you're not feeling well Craig. You've still got two weeks to recover before the meeting.
Way to go finishing your rock Tom! I look forward to seeing the results.
I shoot my corals with a Canon EOS 50D in manual using RAW. While I was getting used to using the camera, I used Av mode (aperature priority) primarily, which allowed me to choose the aperature / fstop (and thus depth of field) and the camera would select the appropriate shutterspeed to yield a decent exposure. If I were shooting fish, I might use Tv (shutter priority), where I'd set a shutterspeed, say 1/200th of a second to freeze the fish (they move and often are blurred in photos), and the camera would select an appropriate aperature to match that shutterspeed for that shot.
When shooting in manual, I'll click off a shot and evaluate it. If it's too dark, I'll either decrease my fstop (larger aperature, less depth of field) or use a slower shutterspeed. I could also change the ISO.
Aperature, shutterspeed and ISO are the "holy trinity" of exposure. Changes to any one of them affect the exposure. I prefer to use as low an ISO as possible and generally keep mine set at 100. Higher ISOs are good when shooting less bright scenes but increasing the ISO also increases the noise or "graininess" of the image. High quality cameras are less noisy at higher ISOs.
Turn off your pumps and give your tank a few minutes to settle down. My corals tend to extend their polyps when the current stops, which makes for better pics, IMHO. Also, it gives marine snow (little bits of crud) a chance to sink to the bottom and there will be less of it in the final pic.
Using a tripod allows for much longer shutterspeeds which allows for smaller aperatures (higher fstop numbers) and thus more depth of field.
Depth of field is the amount of subject in focus from the point where the focal plane is set. Some shots look great with a narrow depth of field so things away from the focal plane are more blurred. This can result in a beautifully diffuse background. Other times a large depth of field is desired, so that as much is in focus as possible. The aperature / fstop determines how much DOF there will be. With very small aperatures (higher fstop values), a phenomenon called diffusion occurs where some detail is lost. Think of taking a pic of someone in a fuzzy sweater. With a tiny aperature (say f22-f30), you will see less of the detail of each thread in the sweater. Lenses have a sweet spot around f8 where maximum detail is captured. I'll use f11-f14 if I am looking for good DOF with marginal diffusion and do use f16-f18 if I need to.
For full tank shots, I'd go with a higher fstop / smaller aperature to get more of the contents of the tank in focus. I'd start with f11 and see how that goes. You can always bump it up.
When using a tripod and shooting stationary corals with no current, I'll often use a shutterspeed of several seconds if need be, although usually I'm using 1 second or less. These are just guidelines and what will work best in your tank depends on your lighting and where in the tank your subject is. Subjects on the bottom or in caves will require more exposure - longer shutterspeeds or larger aperatures (smaller fstop numbers) - compared to those just under the water surface right below a reflector.
Shooting in RAW is great because what gets saved by the camera is the unprocessed image sensor data, which allows you to make the adjustments (such as setting the white balance and tweaking exposure), instead of relying on the camera to do so (which is what happens when saving as jpeg in camera). If you're not happy with the settings you've applied while post processing, simply reopen the raw file and use different ones. There's no loss of image quality and you can do that as many times as you'd like.
Setting the white balance is one area where RAW really is awesome. While most cameras do a great job with white balance and exposure in bright outside scenes, they do a horrible job with white balance when shooting under high color temperature lights, such as 20,000K MHs. This is the reason most peoples' reef tank shots are so blue. When I open a RAW pic (I use Photoshop but I believe you can use Digital Photo Pro which probably came with your camera), I set the white balance by moving the color temperature slider until the pic looks like what my eye sees. It's that easy. And the colors are incredibly accurate.
My goal is to produce an image that looks as close to what I see as possible. Some people go nuts with post processing, playing with color saturation and other manipulations that may make a pretty pic, but it's not what they were looking at when they took the photo. There's nothing wrong with that per se, unless one is trying to be as accurate as possible.
After I've set the white balance I may crop some (if appropriate), tweak contrast or brightness and sharpen a bit, but that's about it. I save my white balanced, "completed" pics as Photoshop documents with full image quality, which are good for printing. When I want to post something here (or create a "screen quality" version) I'll resize the image down, reducing both the pixel size (preserving the aspect ratio of the image) to say 900x600 for 4x6 or 1.5:1 aspect ratio shots and dpi (my camera shoots in 240dpi but screen resolution is 72dpi). I'll sharpen the new size and then save as a jpeg, upload to Photobucket and then paste the IMG code into my RC posting.
This may sound like a lot but once you get the hang of it it's easy and flows smoothly. For a more comprehensive guide to reef tank photography, I suggest reading the material at
Ximinas site.
I hope this helps. Good luck and have fun with it!
Ken
