Captured NGC 253 Scuplptor Galaxy for the second time within a week or so , but this time 220km away from my NexDome Obs under Bortle 3 Skies and a bigger scope.
I was at my dark site retirement retreat for 4 days but only had one clear night where conditions were extremely poor. A first quarter moon descending in the north west with heavy dew by 10pm made for tough imaging conditions, not to mention poor seeing,. My guiding reflected the poor conditions
Nevertheless I was keen to image this galaxy for the first time with my 10" Scope under dark skies.
My session only lasted a 3 hours
NexDome Obs
Bortle 3 Skies
Conditions poor , heavy Dew and poor seeing
First Quarter Moon
10" f5 Klaus Helmerich carbon fibre Newt ( focal length 1250mm )
Skywatcher EQ8-R Pro Mount
ZWO 2600MC cooled to -10C , Gain 100
No Filter ( only internal UV/IR Cut protective Window )
Guide Scope: 60mm Orion with Helical focuser
Guide Camera : ZWO290MM
100 x 90 sec subs ( dithered every 2nd sub ) About 2.5 hours of usable data
20 x Flats
20 x Bias
EQMOD and Stellarium
APT
PHD2 Multistar Guiding ( 1.00 to 1.50 arc sec total , terrible guiding ( see sawing ) but still managed nice round stars , they are just more bloated than with tight guiding )
Stacked in Deep Sky Stacker
Processed in Startools v1.8 OSC Linear data set
Quite please at how much faint detail I could expose with such limited data under poor conditions with the bigger scope. ( Gives me confidence when conditions are good and can capture significantly more data eg: 6 to 10 hrs ) It was satisfying dealing with minimal gradient compared to my City Suburban Bortle 8 location !!
Astrobin link below for better resolution ……
https://www.astrobin.com/g3cti7/
Comments welcome
Thanks for looking
Martin