While photographing sea urchins in Hawaii, I was reminded that shooting images under water is tricky due to the number of variables that come into play. When I first saw these sea urchins, I thought: No problem. I’ve photographed things under water before. We even had an earlier post about photographing sea anemones in Australia.
I found three sea urchins that formed a nice triangle. When I first arrived on the scene with a group of students, I shot a quick photo and everything looked fine because the angle of the sun was fairly low.
After helping some students, I later tried to shoot the urchins again but realized there was no way I could get the images sharp. When I zoomed in close, I realized that the light was diffracting and creating rainbow-like halos. You can see these in the image above. I tried several potential solutions… different shutter speeds, different angles, waiting for the water to be still, even focusing manually… but nothing seemed to work. The halos were still a problem.
I stepped back to consider what was causing these halos and I realized that the angle of the sun had shifted since I took my first shot. The sun was now fairly high in the sky which also caused a fairly bright background behind the sea urchin. The bright sun combined with its current position was creating a prism effect reflected from the water. This prism effect was the cause of the halos.
I needed to find a different sea urchin and use a different perspective to photograph them. I found one in shallower water surrounded by a darker background. In this environment, reflected light would not be a problem. Because the sea urchin was in shallow water, I was able to shoot it directly from above which then put the sun behind me. This minimized the softness created by these rainbow halos.
So, this is an important lesson… when you’re out in the field, there is no one formula that provides the solution to every problem. Even if it’s something that worked in the past, this is no guarantee that it will work again. Out in the field, you must be able to think and figure out how to get around each problem. Field work is a great place for out-of-the-box thinking.