M83 (re-processed with PixInsight)

[John K]

Hi everyone,

M83 (cropped) taken with a 9.5" CDK telescope, AP900 mount and an ASI 1600mm camera. 1.5 hours each of RGB channels and 3.5 hours of Luminance. Total 8 hours. all exposures 3 mins long. Image taken from the ASV's Leon Mow Dark Sky Site in Heathcote, Victoria, Australia.

Image re-processed from original data taken June 2019 with PixInsight.

This is the first object I have fully processed with the PixInsight software and what an amazing software it is. Have several years ahead of fully learning how to use this incredible software.

Some finishing touches also applied with Photoshop.

High version here:

https://www.flickr.com/photos/johnka...blic/lightbox/

Clear skies.

John K.

[Geoff45 (Geoff)]

Great first PI image John. In fact great image whatever the software, Colour is spot on and and there is lots of fine structure showing. Some problems with the bright star cores though.
Geoff

[Ryderscope (Rodney)]

Looking at this on my phone John and it looks like a great M83. Glad to see that you are diving in to PI. I’m sure that the journey will be fruitful.

[alpal]

Hi John,
are you saying that the original is here:
https://www.flickr.com/photos/johnka...posted-public/

And your PI version is here?
https://www.flickr.com/photos/johnka...posted-public/


If so then PI has enabled you to do an amazing processing job.


cheers
Allan

[Paul Haese]

Colour is indeed good and not too over sharpened but I think the focus appears a tiny bit soft at full resolution. What was your FWHM values on each sub?

[Placidus (Mike and Trish)]

Very fine indeed.

We think the problem with the stars is not FWHM because the faintest ones look good, but clipping of the whites to produce "sequins". This can happen early in processing due to setting the white point incorrectly, or it can happen later as a result of sharpening, in which case a star mask can help.

[h0ughy (David)]

Cool, I would be ecstatic with that result

[John K]

Originally Posted by Geoff45

Great first PI image John. In fact great image whatever the software, Colour is spot on and and there is lots of fine structure showing. Some problems with the bright star cores though.
Geoff

Thanks Geoff

Originally Posted by Ryderscope

Looking at this on my phone John and it looks like a great M83. Glad to see that you are diving in to PI. I’m sure that the journey will be fruitful.

Thanks Rodney

Originally Posted by alpal

Hi John,
are you saying that the original is here:
https://www.flickr.com/photos/johnka...posted-public/

And your PI version is here?
https://www.flickr.com/photos/johnka...posted-public/


If so then PI has enabled you to do an amazing processing job.


cheers
Allan

Thanks Allan. Yes that was the original go with Photoshop and Deep Sky Stacker.

I simply followed most of the Warren Keller's mono workflow to the best I could at this early stage - the key difference appears to be how the Luminance is processed and then applied to the RGB by PixInsight vs Photoshop (and my skill level in both as well!)

Originally Posted by Paul Haese

Colour is indeed good and not too over sharpened but I think the focus appears a tiny bit soft at full resolution. What was your FWHM values on each sub?

Hi Paul - to be honest was not too selective with the sub frames - went for quantity rather than quality - all sub frames from memory had an eccentricity of below 0.6 and that's all I remember quickly looking at

Originally Posted by Placidus

Very fine indeed.

We think the problem with the stars is not FWHM because the faintest ones look good, but clipping of the whites to produce "sequins". This can happen early in processing due to setting the white point incorrectly, or it can happen later as a result of sharpening, in which case a star mask can help.

Mike n Trish - you are right on to it! - totally correct - it was caused by deconvolution which I did try to minimise - I still have not played around enough with the Deconvolution function and settings in PI to minimise that effect on the stars and agree a star mask would have been the way to go here although I did want the stars to be sharpened somewhat as well.

Originally Posted by h0ughy

Cool, I would be ecstatic with that result

Thanks Houghy