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Re: Slow response

Posted: Fri Aug 11, 2017 12:07 am
by Ray Hansen
I am using darks, and have the min star size at 2 pixels.

Robin, I'll send more images, but won't have good weather again for at least a week.
It's the time of year we get rain in the desert.

Re: Slow response

Posted: Sun Aug 13, 2017 12:52 pm
by oopfan
My winning combination is:
1. 400mm scope with 0.5x focal reducer yields 1.7 degrees on the diagonal of my ASI120MC
2. 2sec exposure 100 gain with dark frame subtraction
3. Minimum star width: 4 pixels
4. Wait until beginning of astronomical twilight (Sun is 12 deg below horizon)

Within 20 minutes I can get my polar alignment error below 20 arc-sec. (It could be faster if my mount had fine adjustment knobs in azimuth).