Superb Image mate. I love the dust lane details and colours you are getting
Thank you Tony. This was a fun capture. I wouldn't hesitate to re-visit this target one day and clean it up a little further. I think I am again a little over-stretched.
Like you say mate more data always helps and that's the great thing about digital astrophotography, you can always add more even if it's years later
Top job mate
I concur, great job.
From a perfectionist's perspective, when viewed at 100% screen, the stars at
lower left are perfectly round, but all the rest are a bit elongated in an 8am
to 2pm direction, suggesting a little bit of diagonal tilt.
raymo
Raymo, I agree with you and I had noticed it already. I was wondering if the eagle-eyed photographers would notice enough to mention it and I’m glad you did. Any suggestions on fixing this would be most welcome. Interestingly, some subs don’t have this eccentricity, but many do. Elongation rotates with camera. Polar alignement is excellent (no mouvement with unguided test subs). Guide scope image is centered. Guiding occasionally has bumps at irregular intervals that could be causing this. I think I’ll be scratching my head for a while. My main suspicions are either the guide scope “bending” as the OTA rotates and/or the focuser is tilted and bends a little with rotation. Comments welcome.
First check the obvious things. Is the T-ring a snug fit when clicked into
place, with no discernible slop or movement whatsoever? How snug a fit is the
camera snout in the focuser? Do 1-2- or three screws hold the snout into the focuser, or is it a helical tightening setup? Screws can of course kick the snout off to one side. Are the focuser retaining screws tight?
raymo
Raymo, thank you for your comment. The fits seem good. Two screws hold the snout. I usually go very tight, but now am wondering whether that could be causing the tilt. I’ll have a look. Thanks.
If the screws contact the snout nearer one end or the other of it you are much more likely to get some tilt than if they contact the snout close to half way along its length. The screws need to be tight, no slop whatsoever. It is fine if the screws hold the snout to one side of the focuser tube as long as the snout is hard up against the tube for all of its length.
raymo
