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View Full Version here: : Barnard's Galaxy - Quick & Dirty


Doogs38
25-07-2023, 08:15 PM
Astro opps are a bit scarce atm but did manage to get 7.3hrs of LRGB data (EdgeHD 8" SCT) for IC4895 (NGC6822) Barnard's Galaxy (my current project). It's a faint target and has been painful to process ... it needs a lot more data which I'll attempt to get over the next few weeks. Just sharing for fun since there aren't many attempts at Barnard's Galaxy in here. Alex

oska
26-07-2023, 02:19 AM
Congrats mate on the less usual target selection, never mind the very decent start. Thanks for the early look. :thumbsup:

Mickoid
26-07-2023, 08:11 AM
Good to see something different posted and you have captured it nicely. Great star colour and not too heavy handed on the processing.

xelasnave
28-07-2023, 08:43 AM
A difficult object in my view but you have done well.
Alex

Dave882
28-07-2023, 10:17 AM
Great work. This is a tough target and you’ve done well with this result with a nice balanced colour and bringing out its rather diffuse shape and structure. Those little Ha regions (possible snr’s?) are intriguing. Might be interesting adding some Ha data to bring them out. Very cool!

Doogs38
29-07-2023, 08:59 PM
Thanks Dave and Alex. Yep, this one is not straightforward and I'm collecting more data (last night and tonight) - Ha, Oiii and LRGB data. Luckily the moon isn't in close proximity and the subs are looking ok with the usual gradients to control. I did a quick preview with Ha added and it brings out the reddish active star forming regions quite nicely ... apparently they're not SNRs Dave, but very active stellar nurseries within curiously round-ish gas clouds (source (http://asterisk.apod.com/viewtopic.php?t=42068)).

Doogs38
10-08-2023, 07:51 PM
Annnnnnd here is the final result for Barnard's Galaxy with about 18hrs integration taken over three sessions. I had lots of problems producing this image and lost count of the number of times I (re)processed the data: wonky stars, flats that didn't work well, poor results from BlurX and NoiseX, combining Ha with LRGB bla de bla bla. But the upside is, I've spent the last few weeks learning the basics of PI's 'old-fashioned' (which sums me up nicely) methods to reduce noise, sharpen and combine NB with BB data using TGV, MMT, de/convolution and masks, masks and more masks ... so much trial and error that my brain is now fried, coz that's what PI does ... it fries your brain while smiling at you :lol:

EdgeHD 8" with 0.7 R, ASI294MM, Antlia LRGB

L - 237x60s = 3hrs 57mins (... not enough)
R - 58x180s = 2hrs 54mins
G - 62x180s = 3hrs 6mins
B - 65x180s = 3hrs 15mins
Ha - 42x180s = 2hrs 6mins
Oiii - 58x180s = 2hrs 54mins
Stars: RGB 20x30s

Hi-res is here (https://pbase.com/doogs38/image/173881583/original). Thanks for looking. Alex

oska
12-08-2023, 01:43 AM
Great result Alex, so many interesting formations. It wouldn't be art if you didn't suffer for it, what.