I've finally decided to give off axis guiding a try after many years with the guide scope - mainly because Marc said I should give it a try! I've added an Orion Thin OAG to the front of the QSI683 and strapped my ZWO ASI120mm to the guider. With the guide camera binned 2x2 I have 1.35 as/pix, down from the 3.09 I had with the guide scope and camera at 1x1. This past week I've been playing with PHD2 settings and getting used to guiding with the OAG. I think it has had a positive impact on my guiding performance with tighter peak errors and about the same RMS and I'm getting more reliable results with longer exposures than what I'd usually go for.
Just to have something to show for the clear nights I've been capturing some Ha Helix. This is 18x10 min, no darks or flats so processed to within an inch of its life.
Here's the big version:
https://www.astrobin.com/full/367014/0/
Thanks for looking.