PDA

View Full Version here: : Noisy 3hr Helix


Benjamin
11-09-2018, 08:54 PM
Very noisy crop of the Helix. Only 3 hours of Ha (5nm) through my ED80 with a ZWO1600MM-Pro in pretty bright misty conditions. Pushed the HEQ5 mount with 15 minute subs (12 in all) guided with a finderguider. The very first sub was okay but as it approached Zenith the stars become much more oblong as guiding became slightly more erratic. Is this a case of the mount’s capabilities, as my googling suggests, or can something be done to solve this problem: hyper tune, turning off Dec guiding, weighting the mount in a particular direction (have belt moddded the mount), OAG? Managed to warp the stars into some kind of shape. Was hoping to get some OIII but clouds and events will delay this a week or two. Appreciate thoughts on imaging near Zenith in particular.

Geoff45
11-09-2018, 09:46 PM
It may be noisy Ben, but there’s still a lot of interesting detail brought out.

cometcatcher
12-09-2018, 02:32 AM
I think that's fantastic for an ED80.

Benjamin
12-09-2018, 05:53 AM
I’m kind of happy where it’s heading (some of the faint bow waves coming through) but the behind the scenes star reduction and rounding is something I’d like to do less of. 15 minute subs on an HEQ5 through Zenith? Anyway, I’m not too hung up on perfect little stars but it’d be awful nice to achieve that and go long. It might just be GAS (gear acquisition syndrome) thinking an AZ-EQ6 would solve all my problems :question:

Lee
12-09-2018, 06:57 AM
Excellent work, I would not have guessed that came from an 80mm aperture scope....

multiweb
12-09-2018, 08:04 AM
Very good data. Keep going. :thumbsup:

Bart
12-09-2018, 10:22 AM
I think it has great potential. Keep at it, you could have a cracker on your hands, especially with a small scope.

Benjamin
12-09-2018, 11:28 AM
My feeling then is perhaps it’s worth rounding a few stars post processing (within reason) given the actual Nebula is resolving quite well? I imagine with better guiding there might be more detail but perhaps not at this image scale? The ZWO ASI1600MM-Pro and ED80 combination seems a good match, without too much under sampling.

Paul Haese
12-09-2018, 01:54 PM
Keep at it Ben. Persistence will pay of in the end for you.

RickS
12-09-2018, 09:18 PM
Looks good, Ben.