Hey there folks. i've been at this since February now. I learned a lot, and there is a lot I still haven't learned. I'm using my camera on a microscope trinocular photo port at the top. I'm using the camera on manual, and I try to control the light intensity of the scope LED dimmer. when I set the led light to go brighter, it goes brighter for a second or so, then keeps going back to an underexposed shot. any clue as to what I may be doing wrong.
I have never used a setup like you have but I would imagine that your microscope puts out minimal light. Is this essentially adapter the camera mount and treating the situation as a wide open lens? Again the whole telescope adapter is not something many of us probably have used. I will assume head/adapter is just a pass through and has no aperture. Your exposure will need to be long I image to get enough light to expose, have you kept increasing exposure length until its a 1/2 sec 1 sec 2 sec... etc and seen the exposure start to look correct? I am in no way surprised if you see what looks correct the camera will show you what your eyes can see though the setup, it will not show you what the exposure will look like with the given ISO/ Shutter and aperture.