How soon?
Maybe you want to share with us whether the S60 is a compound scope and
how you connected your camera to it; whether you have an external
shutter and whether you use a speed light to illuminate your specimen.
And whether you want to do brightfield, darkfield, phase, ....
There is no one setting that fits them all. It's almost like in
ordinary photography. It depends on the specimen, its motion, the
illumination, and the setup. The thing that is different from ordinary
photography is that photomicrography is much more challenging.
Especially if you are not using a dedicated camera for this task.
A hint, your D100 has a pseudo mirror lock up (MLU) that delays
exposure by 0.5 seconds after the mirror slapped in place. Although
that might not be enough time to completely eliminate vibrations on a
complex setup, it will help you to get sharper images. But you still
get blur due to the motion of your shutter curtain. The best images are
obtained with a D70 and D100 using an external shutter and operate the
camera in bulb mode with manual focus set to infinity. The external
shutter should be a leaf-shutter and not a curtain shutter.
Gregor