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View Full Version here: : NGC 6357 Lobster Nebula in SHO and HOO


Startrek
22-07-2025, 06:02 PM
Ive spent the last 10 days down at our retirement getaway ( NexDome Obs ) with the tail end of a waning Moon. Although skies were generally clear conditions were really poor with a south west jet stream running most nights. Seeing and transparency ( stars scintillating all night ) was bad and this reflected in my guiding where I struggled to get below 0.85 arc sec most nights and Dec and Ra see sawing ( chasing the seeing )

Chose to image the Lobster as it was well placed early in the night at mid altitudes plus I haven't imaged this object from my Dome with the 2600MM.

Bortle 3 Coastal Rural location
Waning Moon
Seeing poor
Telescope 10" f5 Klaus Helmerich Carbon Fibre Newtonian ( Self Built ) FL 1250mm
Imaging Camera ZWO 2600MM cooled to -10C , Gain 100 HCG
Coma Corrector TS Optics GPU
Antlia 3nm filters
PHD2 Multistar Guiding ( 0.80 to 0.95 arc sec total ) Stars round but bloated ( discarded quite a few bad subs )
Orion 60mm guidescope with Helical focuser
ZWO EFW 7 x 2" filterwheel
ZWO EAF focuser
Tracking and Goto EQMOD and Stellarium
Aquisition and Capture APT
Ha 137 x 2 min dithered subs
Oiii 141 x 2 min dithered subs
Sii 157 x 2 min dithered subs
Full Calibration Suite
Darks from Library
Flat Darks Ha, Oiii and Sii
Total Integration 14.5 hours
Subs reviewed in ASTAP
Subs analysed, calibrated , stacked and aligned in ASTAP
Post processed in Startools V1.8 via Compose using Luminance/Color L+Synthetic L from RGB, RGB.

SHO and HOO versions

Astrobin links for ful resolution…,
https://www.astrobin.com/full/ww3ttg/0/
https://www.astrobin.com/full/f8n6yz/0/
https://www.astrobin.com/full/0xml2c/0/
https://www.astrobin.com/full/dogayn/0/

Attached images 200KB limit
Native frame versions
Cropped versions for a closer look


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

Thanks for Looking

Comments Welcome

Martin

Retrograde
23-07-2025, 12:46 PM
Looks good Martin!

Some nice detail there, despite the conditions. This object is deceptively large - I couldn't fit it all in the field of my 1000mm focal length MN190, last time I imaged it.

strongmanmike
23-07-2025, 02:59 PM
An incredibly intricate nebula this one Martone, you have revealed a lot of the detail too, riiiight down into the Lord of the Rings castle, nice job :thumbsup: I think I like the orange/blue palette best :confuse3:

Shame about your seeing conditions...but, how was the sea during your coastal soiree? :D

Mike

Startrek
23-07-2025, 05:58 PM
Thanks Pete ,
Like you my 8” Newt in Sydney still can’t fit the whole thing into the FOV.
It’s one of my favourites, that greater core region has so much going on too.

Cheers
Martin

Startrek
23-07-2025, 06:07 PM
Thanks Mike,

Ocean was as flat as tac all week , little or no wind in the evening , no dew but upper atmosphere was raging , stars were scintillating right across the arm of the Milky Way from low altitudes to zenith. It did settle a bit after midnight but guiding was still jumping around.It was great to image from the Dome again under dark skies.

Martone

DarkArts
23-07-2025, 09:14 PM
Great images. The SHO close-up is my fave. :thumbsup:

Startrek
24-07-2025, 02:42 PM
Thanks
Appreciate it
Conditions were poor but a little Deconvolution in processing helps sharpen up the detail especially when you zoom in
I prefer the typical Hubble SHO palette as well

Clear skies
Martin