I had to do an overnighter at my retirement retreat down the south coast for some maintenance Quotes / jobs , so as the weather was looking good , took my Astro bag with me just in case.
Opened up the Obs and decided to capture M20 Trifid Nebula again and compare it to my recent Sydney capture.
Clear night but poor conditions
No moon
Bortle 3/4 skies
10” f5 Klaus Helmerich Carbon fibre Newt
Skywatcher EQ8-R pro mount
ZWO2600MC cooled to -10C , Gain 101
Orion 60mm guide scope with helical focuser
ZWO290MM guide camera
EQMOD and Ascom Stellarium
APT
PHD2 Multistar guiding ( 0.75 to 1.0 arc sec ) chasing the seeing Ra see sawing
138 x 60 sec subs ( dithered every second sub )
40 x Flats
60 x Bias
Stacked in DSS
Processed in Startools V1.8 OSC Linear Data Set
One notable difference between Sydney’s M20 image and this image was the noise level, this image was so clean I really didn’t need to apply any noise reduction , where in Sydney it’s a must , generally 4 to 6 pixels
Also just over 2 hours of data ( Sydney was 3.5 hrs ) using the bigger 10” Newt resulted in more fine detail
I also attached the difference in laptop screen views during capture Bortle 7/8 Sydney and Bortle 3/4 South Coast ( green vs black )
Astrobin link below …..
https://www.astrobin.com/8fs7m9/
Attached original frame version ( 200KB compressed )
Attached Crop version ( 200KB compressed )
Attached M20 Sydney sub capture laptop screen
Attached M20 South Coast sub capture laptop screen
Comments welcome
Thanks
Martin