NGC 1365 Great Barred Spiral Galaxy under Sydney Skies
Gusty hot westerly winds abated yesterday afternoon in Sydney to leave a clear night. Decided to image NGC 1365 a barred spiral galaxy in Fornax for only the second time. My rig is grossly undersized in aperture and focal length to tackle this small dim magnitude 10 galaxy under Bortle 8 skies but had a go anyway. Atmospheric conditions started off ordinary but did improved into the evening and by 2.00am seeing was really good.
6” f6 Bintel GSO newt
Skywatcher EQ6-R mount
ZWOASI2600MC set in Ascom to highest dynamic range Gain 0 cooled to -10C
220 x 60sec dithered guided subs ( dithered every 3rd sub)
30 x Flats
40 x Bias
Tracking and Goto EQMOD and Ascom Stellarium
Captured with APT
PHD2 Multistar guiding ( started at 0.90 and an hour later was down to 0.65 to 0.70 arc sec error total ) Ra and Dec almost the same values
Stacked in DSS
Processed in Startools V1.7 Linear data set
Even with heaps of short subs , dithering and calibration, stretched image was fairly noisy which is a bit disappointing
You had some good conditions as well, I see.
Up in the mountains, we had 25 knot winds and gusts until about 2am. Guiding was awful (1.3) until it dropped.
Love the colours Martin, a bit noisy as you said but more data should curb that. It's a beautiful galaxy though. Well done .
Cheers,
Tony
Thanks Tony,
Yeh more data might help , there is a point of diminishing return though
In hindsight I should have flipped and captured another 2 hours but I was pretty tired at 3am having worked at my sons place all day
Martin
You had some good conditions as well, I see.
Up in the mountains, we had 25 knot winds and gusts until about 2am. Guiding was awful (1.3) until it dropped.
Pleased to see you got such good results.
Thanks Adam
Too kind mate , the excessive noise was disappointing though
My NGC 253 sculptor galaxy 3 weeks earlier had very little noise
Maybe to hard on myself as my equipment is not exactly ideal chasing tiny dim galaxies under crap light pollution with a OSC
It’s a challenge !!
Martin
Yeah I think you're being hard on yourself there, Martin
Just under 4 hours on a dim galaxy with 60 second subs from the most light polluted spot in Australia, well noise is always going to be an issue that would be difficult for anyone to overcome.
Plus, after a hot day (Friday was pretty warm!) many roofs radiate heat into the air at night, making shooting conditions even worse. All of that adds up, so you did really well.
