The Lagoon Nebula (M8), The Trifid Nebula (M20) and M21 in Sagittarius

[Octane (Humayun)]

Hi all,

Full resolution image available here.

Note: this is the full resolution image and as such it might be difficult to view in your browser; right-click the image and select View Image to make it fit in your browser window.

This was data that I was capturing while working on another mosaic.

This was also my first time in blending hydrogen alpha data in to the luminance, as well as into the red and blue channels. I think it has turned out nicely.

Target: The Lagoon Nebula (M8), The Trifid Nebula (M20) and M21 in Sagittarius
Date(s): 2018; July: 2nd, 3rd, 4th, 5th, 8th, 9th, 10th, 11th, 13th, 14th and 15th
Location: Gordon, ACT, Australia
Detector: SBIG STL-11000M at -20 degrees Celsius
Telescope: Takahashi FSQ-106N
Focal length: 530mm
Mount: Losmandy G-11 (Gemini)
Guide scope: Takahashi FS-60CB
Guide camera: SBIG Remote Guide Head
Exposure: Nebula L(Ha)R(Ha)GB(Ha) (120 120 120 120 720); total: 20 hours in 300 second subexposures for LRGB and 1800 second subexposures for Ha
Exposure: LRGBHa bin 1x1
Software: MaxIm DL 5, CCD Commander, FocusMax, PinPoint, PixInsight and Photoshop

Comments, critique, etc., most welcome.

Thank you for looking.

H

[Placidus (Mike and Trish)]

Joyous! So much to see!

Nice gentle processing. It looks even better if one sets the dark point a tad darker.

Bravo!

MnT

[leon]

A work of art H, I like it a lot such a beautiful widefield well done indeed.

Leon

[cometcatcher (Kevin)]

That's a great image to pan and look around.

[gregbradley]

Great work Humi. A favourite of the sky and very nicely done.

Greg.

[Andy01 (Andy)]

Nicely done H, delicate & subtle - well done!

[atalas]

Wonderful work H this field never gets tiring....everyone has their own take on It, and It's always interesting taking the tour.

[Stevec35 (Steve)]

Nicely done indeed. It could probably benefit from a bit more contrast but it's still an excellent rendition of this grouping.

Steve

[RickS (Rick)]

I'll look forward to the completed mosaic, H! The image looks great. One minor nit is the partial bad column (look near the small PN in NGC 6559.)

Cheers,
Rick.

[multiweb (Marc)]

Good to see some pics from you. Turned out very nice. I have the same issue on my QHY9 with a recent bad column so I'd be interested to hear how PI gets rid of it. I suspect CosmeticCorrection and use a dark as the rejection map? Rick probably can chime in. Otherwise impute rejected pixels in CCD Stack paints the black pixels and holes left behind with neighbouring ones.

[troypiggo (Troy)]

Awesome. Nice blend.

[RickS (Rick)]

Originally Posted by multiweb

I'd be interested to hear how PI gets rid of it. I suspect CosmeticCorrection and use a dark as the rejection map? Rick probably can chime in.

You can set up a defect map with CosmeticCorrection. I use a few 16803 cameras that have developed shedloads of bad columns over time and it works a treat with a little dithering.

[multiweb (Marc)]

Originally Posted by RickS

You can set up a defect map with CosmeticCorrection. I use a few 16803 cameras that have developed shedloads of bad columns over time and it works a treat with a little dithering.

Will give it a go.

[SimmoW (SIMON)]

Yeah, pity about the lines, CC will fix that. Lovely subtle version of the famous pair!

[Geoff45 (Geoff)]

Superb image Humayan. I love the way that these wide field images bring out the relationships between all those objects which are often separately imaged.
Geoff

[petershah (Peter Shah)]

Lovely work....love your processing

[Octane (Humayun)]

Thank you, everyone, for your lovely comments. My apologies for the late reply; I’ve been without mobile reception as I went 4WD through the Flinders Ranges and then across the desert up north. Will be back home tomorrow. No photography on this trip. I just needed to get away and soak it all in.

The bad columns are from using a 2-3 year old superbias frame. The sensor has deteriorated since then. I’ll make a fresh one soon.