Photography - Technique - Over Under Shots
Most of my diving is drift diving. While being picked up, I sometimes entertain myself by shooting the dive boat with a wide angle lens and dome port. What I'm trying for are some good/fun over under shots and some eye candy for the boat operators and staff.
Most of my shots don't turn out to be over under shots. However I have a lot of fun taking them and sharing them.
Click on image for larger image.
Click here for complete gallery of examples.
In the process of getting better at this kind of shot, I've learned the following.
- The drain holes on the housing port have to be blocked to prevent the water between the housing port and the lens from draining out part way during the shot and creating a horrendous horizontal line. I use a strip of duct tape around the housing port to block the holes.
With the holes blocked this way it is necessary to remove and replace the WAL underwater at the beginning of the dive to ensure that all the air bubbles are out. But, even without the holes blocked I found this practice necessary to avoid all air bubbles.
- Manual mode with a fixed focus distance and no strobes produces the best results. I am now using ISO 64, F 5.0, S 1/400 sec. and a 31 inch focus distance to try to hit he hyperfocal plane of the WAL with dome combination. And I am shooting in normal sequential mode, which yields up to 8 shots at 1.3 frames per second. See Equipment - Settings, My Mode 2 for details.
I started with fully automatic mode with sequential shooting. But the settings the camera picked varied wildly depending on whether the camera was below or above water as I began panning the sequence. For example, if I started shooting underwater as I raised the camera, the camera would set the exposure and focus for an in water shot. The result was that the shots taken at the water line and above the waterline were not properly exposed and were often out of focus.
- I usually use a panning motion starting underwater and raising the camera toward the surface and then above the surface as I shoot about four sequential shots. I shoot this way because, with the waves and me bobbing around, I cannot just try to line the camera up at water level to take the shot. While shooting this way I often think of myself as a monkey at a typewriter i.e. eventually I'm going to get a great shot.
- Shooting with the sun behind me is absolutely necessary. If the direct sun rays hit the dome from almost any angle they produce spots and flares that really mess up the picture.
- I have not found it necessary to use any wetting agents on the dome to prevent drops from messing up the shots. In part I think I am getting good shots because I am shooting in sequential mode while panning the camera out of the water. This doesn't give drops much time to form. Of course the size and shape of the dome helps to keep drops from forming. I'm probably just plain lucky too.
- Sometimes I correct for barrel distortion from the wide angle lens and dome combination and sometimes I don't, depending on which I find most visually pleasing to me. See Image Processing - Wide Angle Distortion for details.
New Photographers Please Note: All pictures shown have been edited. Typically I rotate, crop, resize, remove back scatter and other artifacts, adjust the histogram, remove color cast, adjust brightness and contrast, final adjust saturation, and sharpen. It takes me 5 to 10 minutes per picture to do these steps. My reason for mentioning this this is that your pictures, as taken, may not look as good as these and I want you to know that mine don't either. For samples of before and after pics click