Underwater shot: Potamogeton crispus

[Chris S.]

This aquatic plant is Potamogeton crispus--aka "curly-leafed pondweed." Here in Northeastern Ohio, it is an introduction from Europe. Identifying features include the small teeth along the leaf margins and the crisp, wavy structure of the leaves, reminiscent of crepe paper. This plant is normally found floating in water--so I photographed it floating in water.

I'm posting this in connection with a response of mine to Drbluethumb's thread about photographing coral in an aquarium.



The shot is at about 1:1 magnification with a Nikkor AF-D micro 105 f/2.8 at f/18 on a D200. The plant is underwater, as its "posture" changes a bit when it is removed from a floating environment. The image was taken as part of a study under a grant from the Geauga Park District in Geauga Country, Ohio. As the interest was primarily scientific, I didn't worry much about a few specular highlights--was more interested in getting the diagnostic features accurate.

I brought the subject into the studio, placed it in an aquarium of clean water, and photographed it from the top of the aquarium--through air and water, but not through glass. In a substantial group of tests with various pondweeds, I found that ultimate detail and sharpness were notably reduced when shooting through the aquarium sides. So I shot most of the specimens from the glassless top of the aquarium.

This was back before stacking entered my life, so DOF is limited. Today, I'd likely shoot a subject like this with a shallow stack.

Cheers,

--Chris