Astrophotography Processing Challenge September 2024

[AstroBee]

CALL FOR DATA!
We are in need of processing challenge data. Please consider submitting data for this fun challenge. I personally have another 3 or 4 subjects that I'm happy to share but I really do not want this monthly challenge to become a "AstroBee's data challenge" event. If you have data that you are interested in sharing, please reach out to me via PM so we can discuss it.


This month's processing challenge is one of my all time favorites, M31, the Andromeda Galaxy. I captured this data back in late September of 2022 and was really happy with the quality of the data. I believe my backfocus was a little bit off but that can easily be corrected if you are using PixInsight and happen to use BlurX. If not, the fov is wide enough that you can crop the edges and still capture the entire galaxy.
This data was captured with my StellarVue SV70T with a 0.8x reducer giving a focal length of 336mm @ f4.8.
I used the ZWO 2600mc for the RGB data and separated the channels and the 2600mm and Chroma 3nm Ha filter for the Ha data.
120x120sec of RGB color data and 20x600sec of Ha data was captured from a Bortle 3 site.
I apologize ahead of time for anyone with limited internet bandwidth and less powerful computers. The data was processed with PixInsight and I used 2x drizzle so the files are massive. There are XISF, FIT and TiFF options available with the TiFF files being the smaller files. If you really, really want to give this a go but are unable to handle the files sizes, reach out to me via PM and I'll see if I can get you the undrizzled data.
I'm very interested in seeing what you guys/gals can make of this, especially for anyone that attempts to combine the Ha data with the RGB. I've never been 100% happy with my versions.

One last tip that I recently discovered and it might be helpful for those using PixInsight & BlurX. If you run BlurX in "correct only" mode on the individual channels and then do a combine channel, you will see what looks like really bad chromatic aberration. I found after running BlurX on the individual channels, I needed to re-do image alignment and that re-converges the channels properly.
https://drive.google.com/drive/folders/ ... sp=sharing

As always, have fun! It's a challenge, not a contest, so everyone is a winner!

[StarHugger]

I will give it a go, wish I could help with the data though...

I think I have read, observed and documentaried this target grouping many times over so it will be fun to add this iteration to my portfolio indeed!


Thanks Greg again for your efforts here.

[Jockinireland]

Thanks for sharing this data Greg @AstroBee

It was is nice data, and the Ha really gives it a bit extra.

Processed in Pixinsight as follows

RGB;
Graxpert followed by BXT (correct only) and star alignment (cause Greg said it needed it!) on each channel
ChannelCombination then SPCC and BXT
NXT
HistrogramTransfomation to stretch
Stars removed - Blanshans Screenstars
various curves for contrast and saturation followed by HDRMT to bring out detail
Recombined using Screenstars

Ha followed the same process except for SPCC

I then added the the Ha into the rgb using Blanshans HaRGB tools.

I then took the stars out again to do some tweaking on colurs as the core had gone quite pink.
Took the starless into Photoshop to futher tweak background and colours and did a selective highpass routine to highlight the structureof the dust lanes.

Dack to Pixinsight to put stars back using ScreenStrars and reduce stars a little using StarReduction.

Ending up with this.

The Ha is maybe a bit "in your face" but i quite like it.

A higher (not full as the files were indeed huge) is in my non public AB here

[AstroBee]

Nice work, David. It looks very similar to my version but I think your Ha addition is better than mine.

[StarHugger]

Exellent David, the AB version is a must see thanks for sharing it...

[Graeme1858]

Interesting data. Looks really clean but then I managed to put some green in the background that I couldn't get rid of.

ABE
Masked Stretch
LRGBCombination with Ha as the Luminance
Starnet +
Curves on the Starless
Curves on the Stars
PixelMath
SCNR
Some more Curves
Noise Reduction not required!

Nice one Greg. Thanks for the data and thanks for the Challenge.