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Benjamin
22-07-2017, 07:52 AM
Not sure there is much I can do to rescue this one. Guiding was a bit wild in RA, which seemed to be a combination of the PA being slightly off in Azimuth, and a heavy 8" Newt which really pushed the HEQ5 Pro (I'm thinking the weight exposed the mounts flaws with backlash etc. to a greater degree that my ED100, or punished more severely any flaws with balancing?). Also got some light reflecting across the image (many possibilities from local sources). Despite their relative slowness I think I might stick to imaging with the ED80 or ED100 for a while. Anyway, 20x 5 minute subs through the f5 8" Newt with a CLS filter, calibrated and stacked in Nebulosity and processed in StarTools. Didn't touch the colour module on this (so maybe a bit purple, although I liked the moodiness of it) but did my best to preserve detail in the paws. I rounded the stars although in the original subs they are squished little footballs and exactly the same squished little footballs in every sub :-/

Atmos
22-07-2017, 09:03 AM
You've done a pretty good job and drawing out an image despite what you had to work with :)

Anth10
22-07-2017, 11:18 AM
Ben, that's a top effort, nice details in the paws and all round great shot!
I'd be happy with that any day with or without squished footy's! You're getting a very good result and that's something to be content with.

raymo
22-07-2017, 12:15 PM
An 8" Newt does not push an HEQ5. I never had any problems with weight
for the four years I used my rig. A few people use 10" Newts quite
happily. Backlash is not a factor, as long as the scope is balanced slightly against the drive direction, as most scopes should be. And, obviously,
slight inaccuracy in P.A. is not the mount's fault.
raymo

Benjamin
22-07-2017, 01:00 PM
Thanks for that Raymo. That's encouraging in regards to the mount. I'm 100% sure it's user error but figured the bigger scope really shows that up? When doing the PA via drift alignment in PHD the amount of fine adjustment is a little overwhelming using the TOAG. Would a finder guider alignment be sufficient perhaps (and quicker)? I'll need to get that balance sorted. :thumbsup:

raymo
22-07-2017, 01:50 PM
Regarding the image, you have nice round stars, so, either your guiding was not bad at all, or you have ditched the bad subs. Have you done the
Periodic Error Correction? that should give your autoguider an easier time
of it. If your HEQ5 is getting on a bit, a strip down and regrease with
decent grease can also help. You can also adjust the backlash on both axes
of course, making sure afterwards to take the axes through 360 degrees
to make sure that there are no tight spots; mechanical parts are
never 100% concentric.
raymo

Benjamin
22-07-2017, 05:30 PM
The round stars came from processing in StarTools. The subs had stars that were are footballs! I'm going to image it again with my ED100 tonight to see if I can get more fine detail. I'm assuming from the original star shapes a lot of fine detail was lost.