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The Good, the Bad, and the Ugly - M101 - Luminance


AstroAndy

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Hi Folks.

Here are 27x 5min & 1x 10min ( a test shot that worked out I threw into the stack) of M101, 2h25minutes in all (remind me again why I shoot galaxies during no astro darkness), garnished with 11 flats.

Again with the big boy (C11, EQ8, Atik 383L+ at -20 degrees, 0.7 reducer, OAG guided w/ ASI 294mm pro & PHD2).

Let me know if you see something good. 😂

Andy

M101L 27x5m 1x10m 2h25m 11 flats proc1.png

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  • AstroAndy changed the title to The Good, the Bad, and the Ugly - M101 - Luminance

Well it might not be what you were hoping for Andy but don't beat yourself up - there's plenty of structure to be see in the central region.

I would certainly put it in the 'good' category - it's not 'bad' and it's definitely not 'ugly'! Examples of the latter two categories can easily be found on a well known astro-image repository - and on my own 'for my eyes only' astro hard drive 😳

Thanks for sharing.

Adrian :) 

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On 05/06/2021 at 19:18, AstroAndy said:

Hi Folks.

Here are 27x 5min & 1x 10min ( a test shot that worked out I threw into the stack) of M101, 2h25minutes in all (remind me again why I shoot galaxies during no astro darkness), garnished with 11 flats.

Again with the big boy (C11, EQ8, Atik 383L+ at -20 degrees, 0.7 reducer, OAG guided w/ ASI 294mm pro & PHD2).

Let me know if you see something good. 😂

Andy

M101L 27x5m 1x10m 2h25m 11 flats proc1.png

Looks pretty good to me, but maybe a bit low in contrast, so maybe you could get something more punchy with further processing. FYI I also took some test luminance images with my C14 on Saturday night (actually early Sunday morning) and this is what I've extracted from 2hours data (12x10m subs). I captured at Bin 2x2 then as an experiment, I further binned 2x2 in software, before post processing....

1548609119_M101_L(withstars).jpg.e466c5e61f61214241b10ccd6677c227.jpg

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Thanks, Adrian and Tomato, and of course, Geof. :)

@Geof, Yes, you're right, I've been mulling over the low contrast issue for awhile now.., I've come perilously close (or even went one step further) to clipping the black point, due to a combination of bad gradients and nasty flats, so I'm thinking of reprocessing it, rather than masking the galaxy and brighten it only.

My image was taken at bin1.

Thanks for your example, that gives me a comparison. Maybe I'll reprocess, or do a new set of 1, or 3 min.

Andy

 

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Hope you don't mind but I ran your original through LinearHistogramEqualization in PixInsight to try to increase the contrast and then I ran it through Topaz DeNoise AI with a minimal amount of denoise (2) and sharpening (3).

m101-aa-lhe-DNAI.png.54b5f5e3d20c0f8a094b929575db8a42.png

Adrian

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Hi Adrian

Nah, I don't mind, always in the business of improving. :) I quite like your rendition, in fact, even though I know the shortcomings of mine, I'm partial to that image. Being lazy, I only ran the sharpening and denoise once, rather than in iterations. Maybe I'll save that for when I get the colors.

Maybe also get some decent flats (the 11 ones I had worked well, the other ones where too close to the horizon, duh).

I don't have Pixinsight, I mostly work in Photoshop and a bit in Faststone Image Viewer.

Andy

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