this animal is 1mm long, but too big for my objective....
Focussing is simple: the camera is fixed: focus, time, aperture - everything.
You start focussing with the microscope above the object and turn the nice wheel below the wire release.
This is the fine tuning focus rail? (oh my english!...)
After a fast cycle of turning and releasing you will be below the object focus in 25 steps.
HeliconFocus does the rest.
I am plannig to do this with freehand macros too, there are old series, shot with continous shooting. My first attempt to find the focus (one of 20 pictures has to be good!).
(this is a stormy and rainy night here!)
..by the way: most of the time is used for setting light conditions now. The picture above is a real portrait with different light sources. The wings had to be revealed! I wanted to have the second fly in this shaded - ghost like appearance (actually it is the haloween mask of Nick Trop).