About technics, I see you use a curious mix of Nikon, Zeiss and Olympus objectives. Do you use them in the same microscope? (finite or infinite?).
Do you need to change your photo system to deal with different coreection approaches between makers?
I use two microscopes, the tube length 160 mm, for I have only one DIC, followed by other techniques. The image registration for the time being I have no problem because all the pictures I paying regular compact camera through the eyepiece of the microscope / Panasonic Lumix TZ8 /.
Great pictures. The Nikon X100 Planapo is giving super results in DIC. I think the bit of extra magnification that you are getting with your compact zoom camera through the eyepiece technique is actually helping you to visualise all the detail the objective is capable of resolving. How much zooming are you using to remove vignetting? I'm guessing 1.5-2X which is really boosting your total magnification without apparent loss of clarity.
Intermediate magnification is 1.25x microscope, the camera I always set to 1X, I can not currently on this item give additional magnification. Only macro zoom and digital zoom is with considerable loss of quality. It can be assumed that the last images are 1250X magnification.
The contrast you get with the 100X DIC is incredible. I think the first is my favorite however since it shows the wonderful "twisty" form these euglena have when they move about.