It mathematically analyzes the curve and determines the best focus position-the minimum point of the curve-and then moves the focuser to the best position. NINA snaps a picture, analyzes the star fatness, moves the focuser slightly, analyzes star fatness, moves the focuser slightly, and repeats until if builds a curve of star fatness vs. Like I said, I use NINA and it has an autofocus routine. How do you deal with the backlash? I was thinking of going another route by locking the mirror (don't know how to do that yet) and use a Focuser on the main tube.

I have a 260 too and I'm still looking for the best focuser option. Vixen down to New Mexico for Galaxy Season. I'm definitely looking forward to solving the counterweight issue, installing autofocusing, and taking Ms. But wow-what happy result for a Q&D experiment! These pics are strictly a Quick & Dirty trial, in the sense that (a) I focused only once, manually, for the entire evening, and my focus was only a best estimate because I didn't have a focusing mask (b) RA balance was problematic-I discovered I will need an additional counterweight to achieve perfect balance with this scope and (c ) polar alignment was far from perfect-due to the cold and the fact that I was only experimenting first night out, I only got the PA 'pretty good' and not 'as good as possible.' And, of course, the time on target was short. Having accomplished the main objective of the First Light exercise, namely, to verify that I could achieve focus with my camera and that collimation was good, I went ahead with a couple of experimental pics. First Light for the VMC260L was successful.īelow are two First Light pics, one of NGC 891, with about one hour time on target, the other of M81, with 32 minutes time on target-at which point the computer shut down due to the intense cold, 10 degrees F (-12 deg.

Vixen vmc260l cloudy nights