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marc4darkskies
26-10-2022, 12:40 PM
"It's raining again (https://www.bing.com/videos/search?q=it%27s+raining+again+song&view=detail&mid=79956A63D63C62C0B91E79956A63D63 C62C0B91E&FORM=VIRE)". Aaah the 80s! :love:

Yep, weather still sucks, so still reprocessing <sigh>.

This is an early 2008 vintage image with my TOA-150. I still had my training wheels on and my image acquisition, processing skills and bag of tricks were just getting started. Basically, I didn't gather enough data (only 6hrs all up), the raw masters were where built without much data rejection (not enough data), and the processing was very ordinary. The framing sucked too because camera rotation was manual and I didn't want to waste good imaging time getting it right. Anyway, the result was kind of respectable for its time.

So, I went back to the LHaRGB masters and let 'er rip. I processed a larger portion of the field (see rightmost image below - apologies to NGC 3603!) compared to my original, more severely cropped 2008 presentation (see the comparison images). All up, a slightly deeper, less noisy version with more accurate and nuanced colour, and more numerous stars (reduced appropriately) with improved colour and no halos etc etc.

Below you'll see a side by side comparison of the original cropped 2008 version (left) and reprocessed version (middle).

BTW, I love stars! Starless images are boring! :shrug:

Thanks for looking!

Full Res:
https://www.flickr.com/photos/marc4darkskies/4662605903/in/dateposted-public/

PS: Annotated version:...
https://pbase.com/gailmarc/image/173097857

Dave882
26-10-2022, 11:11 PM
That’s a really superb repro. I agree there’s improvement across the board - colour, detail, stars- a real winner! I especially like the blue that has come through around 3581/3572/3584. It’s almost like you’ve added more data. Great job

Ryderscope
27-10-2022, 09:04 AM
Excellent update Marcus and a good use of these rainy and cloudy times. The reprocess has brought out the fainter structures around the main nebula and lifted the contrasting colours :thumbsup:

marc4darkskies
27-10-2022, 10:11 AM
Thanks very much Dave! Glad you think so! :thumbsup:

Nope, no data added - just a lot more experience! :) The only NB added was Ha. It's worth pointing out (at the risk of stating the bleeding obvious) that the contribution from Oiii emission IS visible in broadband data spread between Green and Blue (looks like a cyan colour). There is a method I use to pull this out which is very manual, but I won't go into it now. You'll see me doing this in most of my LHaRGB images where I've pulled out the subtle blues & pinks to avoid the everything-is-red look.



Cheers Rodney! It is fun to do. :nerd: My wife sometimes wonders how I can sit at the computer for hours re-processing, but she has an appreciation of what I do (thankfully). My main goals are to improve depth, colour and detail of course - which is easy with the older images - and it's very gratifying when I succeed.

gregbradley
27-10-2022, 01:44 PM
That's a signifcant improvement. I like the last wider image the best.

Greg.

Crater101
27-10-2022, 02:25 PM
I have to agree, there's a marked difference - for the better - in the reprocessed images. Nice work!

marc4darkskies
28-10-2022, 07:53 AM
Cheers Greg! Me too :)



Thanks Warren!

rustigsmed
28-10-2022, 10:35 AM
yes - great repro - i especially think the colour improvement is huge to my eyes.

marc4darkskies
28-10-2022, 05:12 PM
Thanks very much Russ! Yes, I think overall the colours are now more accurate & nuanced.

Startrek
28-10-2022, 05:33 PM
Marcus
Great job at reprocessing this wonderful Neb
Well done !
I have to agree I’m not a fan of Starless images. They look like spray painted Art.
A lot of folk re processing ( me included ) due to weather, it’s actually a worthwhile endeavour , you always seem to find minor improvements here and there.

Cheers
Martin

marc4darkskies
29-10-2022, 11:05 AM
Hey thanks Martin! Much appreciated! Yep, starless images leave me cold! :cold: I have to chuckle at those who have removed stars from JWST images. I wonder if they also remove trees from pictures of forest scenes :lol:.

Andy01
30-10-2022, 02:35 PM
New & improved version sure looks the goods, well done! :D