The second is a small marine amphipod found in a sample of seawater and algae. (The eyes are very interesting in these creatures, and quite different in appearance from the freshwater relatives I've looked at).
The third image is a very close look at a single leg section of a freshwater amphipod. (If I oriented the polarizers a certain way I obtained this blue/white coloration of the muscle tissue... which I really liked).
Crossed polarizers really add another dimension when examining these subjects. These muscle structures are very transparent and scarcely visible in "normal" brightfield.
One difficulty photographing with this method can be the extreme dynamic range between the brightest parts and the darkest parts where you want to preserve detail. With this type of subject I seldom adjust the polarizers to full "extinction" since then all you can see are the brightly illuminated muscles with no real sense of context. So the polarizers are adjusted while doing test shots and checking the histograms. (These must have been a real pain to do with film!). Even working this way, it is sometimes necessary to take a darker exposure of extremely bright parts and "layer" it into the final image in order to avoid "blown-out" highlights.
Olympus 10/0.40 S Plan Apo, Canon 350D. Brightfield with crossed polarizers. Multiple image z-stack combined with Helicon Focus.
Olympus 4/0.16 S Plan Apo, Canon 350D. Brightfield with crossed polarizers. Multiple image z-stack combined with Helicon Focus.
Olympus 10/0.40 S Plan Apo, Canon 350D. Brightfield with crossed polarizers. Multiple image z-stack combined with Helicon Focus.
