Messier 83 in LRGB

[Sirius_Skies]

A beauty I haven't imaged since ditching the DSLR for a QHY268M a few years ago! The southern showpiece that is the face-on spiral galaxy Messier 83 in the constellation Hydra. There's a lot of structure to this galaxy with well-defined spiral arms, dark dust lanes throughout, and a lot of nebulas (red/pink regions).
This target also happens to be first light with my new Antlia 2" LRGB Dark Series filters!

for a higher resolution image, see my Astrobin account. https://www.astrobin.com/wjv4l8/

Skywatcher 10" F4 Quattro, Tele Vue Paracorr II coma corrector, NEQ6 mount (hypertuned, belt modded), QHY268M (SGP software), QHYCFW3L (7x2"), QHYOAG Medium, QHY5-III 178M guide camera (PHD2 guiding), Antlia 2" LRGB Dark series filters. Stacked/Registered with Deep Sky Stacker/Registar (calibration frames included), post-processing in Photoshop CC.

[TrevorW]

Nice colours Jacob :)

[alpal]

Excellent picture Jacob,
I just wonder if I could suggest improvements without sounding pedantic?


Here goes anyway -
Minor adjustments:

The picture seems a little dark on my monitor.
I would have boosted the brightness slightly with curves and
used a blurred layer mask on the center of the galaxy - local adjustment -
to increase contrast once again using curves.

The dead center of the galaxy has either exceeded the well depth or has
been stretched too much? (255 out of 255 bits.)
Only your original FIT stacks can answer that.

When pixel peeping there are either red rings or blue rings around many stars and
there are also blue blobs at about 10 o'clock on the edge of the galaxy.
I don't know what caused that - maybe a star mask?

cheers
Allan

[Dave882]

Great stuff some really lovely fine detail on display :thumbsup:

[Sirius_Skies]

Hey mate.
Your pixel peeping serves you well! I had a closer look at the stars and yes, there are blue/red rings (not sure how I missed it). Looking through the layers in PS shows they are an artefact that PS introduced when I tried to reduce some chroma noise I saw in the stars (happens sometimes). Removed that layer and no more rings!
As for those blue blobs at 10 o'clock, they are legit. However, I did just patch up a couple of them as StarXterminator partially removed a couple of them so went a bit "blobby".
The center of the galaxy was borderline blown out before stretching (about as bright as many of the stars!). I did have a play with masking it but tended to end up a bit flat. Could play with it a bit more but might just leave well enough alone for now.

Is is the background that seems dark to you or the whole image? I target a background brightness of ~25/255 (or about 10% greyscale), which tends to look about right to me, and looks bright enough on my monitor. Once I get to <15/255 the image takes on a more "inky black" that I prefer to avoid. I brightened the galaxy somewhat, which does bring the galaxy closer to mid-tones.
Cheers,
Jacob
P.S. I uploaded a new revision on Astrobin

[gregbradley]

Looks good Jacob. You tamed the core very well.

Greg.

[alpal]

OK - that's good Jacob,
PM sent.


cheers
Allan

[strongmanmike]

A very nice M83 there Jacob :thumbsup: some good feedback received there too, nice one.

Mike

[Sirius_Skies]

Cheers mate. I've always working on something. I'll be sure to keep sharing pics as they come.