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Dave882
09-05-2022, 12:10 PM
NGC4945 - AKA the Cigar Galaxy

Shot over the course of 3 nights last week - started with about 5.5hrs of data but culled down to 131x 120sec subs mainly due to bad focus shift on one night :sadeyes:.

C14 @f7
Eq8
Asi2600mc pro bin1
Asi290mm with celestron OAG
131 x 120sec subs
ASIAIR Pro
AAP + DeNoise

This is my first go trying to process-out some of the background noise generated by my beautiful bright suburban Sydney skies. I'm trialing Topaz Denoise as its a fairly cheap and easy to use alternative and I really don't have the time to learn a whole new processing methodology just yet.

I've gone very light with the software (no sharpening and masked the body of the galaxy for reduced impact). After blinking between the 2 images till my eyes hurt, i have to say I thinks its a good improvement and can't seem to see any damage done to original data, but I'd love to get some feedback on what you think. :)

Links to bigger versions:
DeNoise (https://1drv.ms/u/s!ArpSiLT3VkGHiPJGnL8l0CqoQ-_kvg?e=hHEIlg)
No DeNoise (https://1drv.ms/u/s!ArpSiLT3VkGHiPJHrkY255KcboKKdQ?e= y87AIz)

Thanks for looking!

PKay
09-05-2022, 01:23 PM
Hi David

For just over 4 hours, that scope really does the job!

Regards de noise:
I always perform denoise (in my case for each filter) at the linear stage.

If done right, it really does help.
Over doing it, well it might be an image wrecker.

I think you have nailed it and the result shows.

Very well done :thumbsup:

Dave882
09-05-2022, 04:29 PM
Thanks Peter- yes I agree it’s a very fine line! Much appreciated

Startrek
09-05-2022, 07:59 PM
Dave,
That a lovely Cigar Galaxy
I like that you haven’t applied Sharpening or Decon , gives it a “softer glowing look”
Colour and detail really good
Haven’t imaged this one since 2020
I can’t change hardware binning in Ascom using my 2600MC , I always software bin in Startools, the Bin module offer fractional binning 25% , 35% , 50% or 71% and trades off resolution for better SNR ( default 50% usually works well as I’m oversampled anyway )
Well done again !!
Cheers
Martin

xelasnave
10-05-2022, 08:31 AM
An excellent image Dave as are all your recent images that you have posted.
Alex

Tinderboxsky
10-05-2022, 09:50 AM
A great capture David.

There are a number of other interesting objects lurking in the background. Most importantly you have just managed to capture NGC4945A in your framing. NGC4945A is an unrelated mag 13 spiral galaxy, partly obscured by the 8th magnitude star in the very top left hand corner of your image. The galaxy is clearly visible and not to be confused as a light flare from the relatively bright star.

Dave882
10-05-2022, 10:59 AM
Thanks Alex- glad you like it! We’ve had a number of nice nights recently so have been trying to take maximum advantage while it lasts. It’s been such a wet and cloudy 6 months!

Thanks for your comments Martin. Yes I’ve noticed that feature to bin and probably should be doing this as I’m sure to be a bit over sampled as well. I think I was just afraid of loosing fine detail but is certainly something to experiment with- it might help my star shape a bit too. I was interested by the pinkish reds that came through after colour calibration- quite unexpected but I left it as is with just a bit of a boost to saturation. Kinda looks like the cigar is lit!

Dave882
10-05-2022, 11:11 AM
Thanks Steve- yes my initial thought was that this was flaring at the edge of my fov (which you can see is a bit of an issue as I’m over the max image circle for the 0.63x celestron reducer with the 2600mc) but when I realised what it was I kept it in there for completeness instead of cropping. And a couple of other interesting background galaxies that I’m happy to have captured there too. It’s always exciting to see what comes out in the final integration as none of these smaller objects are visible until you put it all together!
Cheers mate

ahmed_haider
17-05-2022, 06:03 PM
That's an amazing capture David! So much detail is visible
I'm pretty sure you shouldn't be posting in the "beginners astrophotography" section ;)

Dave882
17-05-2022, 09:55 PM
Hey mate- Cheers for the compliments, thanks very much! While I’m pretty comfortable wrangling big scopes and even guiding them doing eaa live stacking, the whole image processing side of things is extremely new to me just this year. I only know some pretty basic processes so very much need and appreciate the help from those with a lot more experience, hence I think I’ll be in the beginner section for a bit still :D.

AdamJL
20-06-2022, 11:32 PM
I missed this image! Thanks to Alex for providing a link in his thread
https://www.iceinspace.com.au/forum/showthread.php?t=198914

This is excellent, David. I thought I'd opened up a NASA image. Great stuff.

and this belongs in the Deep Space section! Hardly a beginners shot.

AstroViking
21-06-2022, 08:47 AM
Another excellent image, David. Well done!


Cheers,
V

Dave882
21-06-2022, 02:58 PM
Thanks Steve much appreciated.

Cheers Adam I'm glad you liked it. I still feel like a bit of a noob with this stuff (only approx 4months since my first processed image) - and it doesn't always turn out pretty! but ok I'll take the hint and start posting into the deep space section. ;)

evltoy
25-06-2022, 01:56 PM
What an awesome image! You have to be proud with that.

Top Job!

Dave882
27-06-2022, 03:43 PM
Thanks Wayne! Yes was quite surprised how much colour and detail emerged from the stack on this one. It’s funny tho, the more I lock back over it the more I think I actually prefer the slightly noisier version. Just personal preference I guess but was worth the experiment. Cheers