Similar to Andy’s idea of start/end by altitude, perhaps start/end by time to meridian?
It’s certainly not a big deal, but I often keep the scope on the east side. Usually I set a start time that I know is within my meridian limits just to prevent unnecessary flips.
Both my east/west are obstructed; in one particular setup I usually start imaging 2 hours before meridian and the westerly tree line is about 30 degrees. I pick 2 hours before meridian because it means the object clears the roof line of my house by a reasonable amount and is also a safe max for my scope on the ‘wrong’ side of the pier for most objects.
Now, I realize we’re just spitballin’ ideas and I can conceded this is unnecessary complexity, but when imaging over multiple nights, I load up a sequence with multiple targets to maximize the “sweet spot” at meridian and have a number of exposures that will typically take 3 nights to get.
I’ll often put a stop time for one target at 30 degrees, and for the next target I look ahead and put stop time at astronomical twilight. Both of these need to be looked up, and it’s not hard to do. Ideally (yes, I know) I’d love to say, stop when either of these are conditions are true. At that point, because my camera has a shutter, I’ll schedule some darks until I wake up…
Yes, that would be great if SGP also had an option to start/stop events at astronomical twilight (or better, a time offset relative to astronomical twilight), or at altitude or meridian offset (hour angle), taking whichever came first (stop time) or last (start time).