SGP joys and minor quirks


SGP Win10.

Well it’s a new season beginning in the Great White North, and I managed to get a few good subs of M51 with my Edge 9.25 a few nights ago between the clouds, the almost full moon, and city lights. I am currently working on fine tuning the temperature compensation in SGP, and I am hitting the sweet spot where I don’t have to do an auto focus run for hours. I let the temperature compensation move the focuser a step or two between subs, and monitor the HFR and star count using Image History to catch any drift in focus. So far it is working like a charm. Focus stays razor sharp unattended for hours, and I am already counting the extra subs I will be able to take per session with the time saved doing fewer auto focus runs.

There is a small quirk in the setting of the amount of steps in the temperature compensation. I have it set to move the focuser -10 steps for every 1C temperature drop. While this setting is working well for me, the image history visible in the attached screenshot shows that it is only actually moving it -6 steps per 1C, not -10.

There is also a minor issue with the center now routine. If I load an Astrobin link, it checks to see that it is valid. When I then click ok, it minimizes SGP to the task bar, and for some reason it sometimes requires multiple clicks to get it visible again.

Minor stuff in an awesome program. Looking forward to another season with SGP.



Since this happens over seven frames, it is likely a rounding error (since we cannot move the stepper in fractional steps). I’ll take a look to make sure that we are at least rounding as best we can.

I guess I don’t really understand this. The centering routine does not provide any provision for selecting an Astrobin link. Are you talking about target settings?


Hi Ken,

Sorry, wrong terminology I guess. Yes the target settings are what I am talking about. And image history indicated that night that the auto focuser had only moved 12 steps after a 2 degree C drop when it should have moved 20. As I said, this didn’t affect the accuracy of the focus. It was excellent, whether it is actually moving the focuser 12 steps or 20.



update: I just opened a single image with the banding at the bottom using Nebulosity, and it is still there. So that eliminates stacking and Pixinsight as possible causes.