M17 Swan Nebula in SHO and Synthetic LRGB from SHO data

[Startrek]

July has been an excellent month for astrophotography with plenty of clear and relatively stable nights. Decided to image M17 again as it was placed nicely to image over the whole month with not too many obstructions in my FOV.
Captured a decent amount of data this time over 7 nights with conditions quite good , no moon , no dew and stable skies.

Even with 20 hours of data from those 3nm filters and no moon around, the image still had a decent level of fine noise grain which was easy to mitigate.

Pretty happy with the final results.

Bortle 8 City Suburban location
New Moon period
Seeing conditions average to good

Telescope 8” f5 Klaus Helmerich Carbon Fibre Newtonian ( Self Built ) focal length 1050mm
Mount Skywatcher EQ6-R Pro
Imaging camera ZWO2600MM cooled to -10C , Gain 100 HCG
TS Optics GPU coma corrector with Beamtech 15mm spacing ring
Antlia 3nm filters
PHD2 Multistar guiding ( 0.45 to 0.60 arc sec total )
Orion 60mm guide scope with helical focuser
ZWO EFW 7 x 2”
ZWO EAF focuser
Tracking and Goto EQMOD and Stellarium
Aquisition and Capture , APT

Ha 212 x 2 min dithered subs
Oiii 195 x 2 min dithered subs
Sii 195 x 2 min dithered subs

Full Calibration Suite
Darks from Library
Flats for Ha , Oiii and Sii
Flat Darks for Ha , Oiii and Sii

Total integration 20 hours

Subs reviewed in ASTAP
Subs analysed, calibrated , stacked and aligned in ASTAP

SHO version post processed in Startools version 1.8 via Compose module using Luminance / Color : L + Synthetic L from RGB , RGB.

Synthetic LRGB post processed in Startools version 1.8 via Compose module ( created Luminance channel from SHO mono , created Red channel from Sii + Ha and used Oiii for Green channel and Oiii for Blue channel) Luminance / Color L , RGB.

Synthetic LRGB is a fun option to have particularly when you image under B8 heavy light polluted skies and only have limited opportunities ( Weather and Moon ) to image Broadband. It isn’t easy having to capture 1000’s of 30 sec subs , very laborious in review , stacking and post processing.

Attached 200kB versions Native size , Crop and Super Crop for a closer view

Astrobin links for full resolution……..,

https://www.astrobin.com/9pjv0l/

https://www.astrobin.com/7daf3m/

https://www.astrobin.com/b20d3u/

https://www.astrobin.com/i7hhvk/

https://www.astrobin.com/bvazr3/

https://www.astrobin.com/50r6ye/


NB: This image is presented as documentary astrophotography and has not use any AI enhanced or AI assisted technology during post processing.

Thanks for Looking

Comments most welcome

Martin

[TrevorW]

Nicely done Martin :)

[Startrek]

Thanks Trevor,
I might do a repro and look at more contrast , a bit more of a stretch and peg back the Starfield a tad. One tends to go over their images at least once or twice to look for improvement.

My son and his fiancé live at Yallingup and work in the wine industry, it’s been raining and windy for weeks. I’m assuming Perth has had similar weather conditions ?

Thanks again
Martin

[TrevorW]

Yes cold and very wet, couple of clear nights recently but too cold for me to bother, I just changed my setup back to the big scope, galaxy season :)