Thanks for the info.
I use a ASI290 mini camera for guiding.
It seems to work the best when the guide scope has best focus.
Image scale on the guide cam is 1.24 arc secs and main scope is 0.74 arc secs.
So, I would like sub pixel guiding and I get it when the guide scope has best focus and seeing is ok.
I try to get stars with less than 3 HWM.
The Temperature here can vary as much as 15 - 20 deg c over the night in winter. Summer isn’t as much.
So, I can be refocusing 3 or more times a night. SGP is about automation and having a second camera
capture for focusing might be a pipe dream.
I suppose people with remote Ob’s would use OAGing.