Spotted something very odd last night.
Looking to refine my polar alignment on my PMX over the last few days, I have undertaken a few TPoint runs. With about 150 points, I am out by a few tics on altitude which I need to fix up. Still, TPoint gives me RMS of 29 arcseconds which is ok for now.
I wanted to take a few shots to see how Protrack impacted on tracking. As you might expect, there was some minor drift in 120second images - I'm imaging at 1600mm f/8 using a QSI 583. Binned x2 I have an image scale of 1.4 arcseconds/pixel.
So I turned on my guide camera - an Atik Titan on a short tube Orion ED80 and banged out another image. Still had some drift?!
I reasoned that there is an issue with my guide cable and then used the manual move function. No dramas there - ask the mount to move and the target star duly moves.
So then I looked at the graph - no major movement at all. It just tracks very nicely at about 0.1 pixel variations. I'm using Maxim for guiding.
I'm stumped on this. The Maxim graph shows not only the movement in the target star but also the guide instructions issued to the mount. It doesn't suggest that there is any issue. I thought I might have a cable snagged or something similar but that shoudl have shown up in the graph.
But the pic clearly has elongated stars.
What could be doing this? I'm wondering whether mount is not receiving the move instructions in the ordinary course - but that still should show up in the graph.
I did notice that opening the TCS Bisque window in TSX that the guider relays are not illuminated when a guide instruction was sent - I didn't check it when the manual move instructions were sent. I'll try that this evening.
I am guiding using guider relays and the ST-4 cable. Guiding rate is 0.5.
Has anyone else seen this?
The funny thing is, its a new development. Go back tio December and everything worked fine.
Pete