Old 13-07-2019, 05:55 PM
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M83 reprocess

I knew that my image processing skills are lacking so I finally decided to stop blaming bad images on bad data and to spend some time learning to process images properly.

Here is the original and the reprocessed image of M83 (7.7h exposure, Bortle 7). More imaging details are in my original post from a year ago.

The new image has been processed in PI following video tutorials from Harry's Astro Shed (and stacking instructions from Light Vortex Astronomy).
This is my first complete processing attempt in PI, done step-by-step while watching Harry's videos and taking notes for the future. I would say there is plenty of room for improvement with more skilled hands.

Hope you like it

P.S. This is in no way comparison between StarTools (original image) and PI (new image).

edit: Added another image with boosted saturation. A significant improvement again thanks to the comments
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Click for full-size image (M83_2018_04_13_14_20_D3_crop_DBE_PCC_HT_MF_ACDNR_HT_Morph_Curves_LHE_SCNR_BN_Curves.jpg)
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Click for full-size image (M83_2018_04_13_14_20_D3_crop_DBE_PCC_HT_MF_ACDNR_HT_Morph_Curves_LHE_SCNR_BN_Curves_Curves.jpg)
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Last edited by luka; 14-07-2019 at 01:47 PM.
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Old 14-07-2019, 08:59 AM
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Anth10 (Anthony M)
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Certainly more detail revealed now with your reprocessed image compared to your initial attempt. Id like to see some of the colour enhanced to give it a lift.
Otherwise you are on the right track, well done.
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Old 14-07-2019, 09:26 AM
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Rigel003 (Graeme)
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Yes, the first image was heavily clipped at the black end and this has improved, as has the smoothness of the image. However you've lost most of the colour. Spiral galaxies should be yellow at the core and blue in the spiral arms. Just increasing the saturation will help show this.
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Old 14-07-2019, 01:54 PM
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Thank you Anth and Graeme. I have uploaded another image with boosted saturation, a big step forward again.

With this last step I have noticed something funny happening with the centres of the big stars. They look white, like they are over-exposed or over-stretched???
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