Not only is the egg mass interesting and beautiful but also the cell structure of the algae is as interesting as well. What algae is that, Fountain moss or ...? By the way the math is far beyond me.
All three are darkfield. (Actually the one with the 40X would not be "officially" darkfield since the stop in my condenser won't do darkfield with my 40X. But since the subject is so large it fills the objectives view, and it is simply illuminated from the back).
Ken,
My "relay" optics magnify the image by 2.1X so that the reasoning behind the math. (The Olympus BH2 intermediate head for DIC magnifies by 1.25X and I use the 1.67X NFK photoeyepiece. 1.25 x 1.67 = 2.0875)