Paul M Posted September 8, 2021 Share Posted September 8, 2021 My session last night was plagued by sky glow. I intended having a lot more time on this target but live stacking with ASTAP confirmed that the sky brightens was killing it. Blackpool's inglorious illuminations strike again, and they're having an extended season this year to make up for Covid restrictions. Right through to January now Anyway, chin up! 19 x 240 sec. 250 PDS Newt on NEQ6 Pro, guided. ASI071 camera binned 1x1 and Optolong L-Pro filter. It's taken much effort to remove the vignetting. I left the scope out all night and all day, then did the flats when I got home from work, tripping over mad dogs, mad children and mad wife. The flats haven't worked so well. AstroFlat Pro plug-in in P.S. saved the day but it does have a habit of clipping the black point if not really careful. It could be so much better but it's a start. I've identified a number of M31's globulars in the image. I might annotate them when I have more time and energy. 9 Link to comment Share on other sites More sharing options...
symmetal Posted September 9, 2021 Share Posted September 9, 2021 Well done for focusing on an overlooked object, normally relegated to being Andromeda's bland side-kick. 😊 I think you would benefit from some dithering to reduce the colour noise in the background. My image of M31 I recently completed showed a hint of blue at the centre of M110. Your image colour balance is a bit too yellow though to possibly show it. Alan 1 Link to comment Share on other sites More sharing options...
Paul M Posted September 9, 2021 Author Share Posted September 9, 2021 8 hours ago, symmetal said: My image of M31 I recently completed showed a hint of blue at the centre of M110. Your image colour balance is a bit too yellow though to possibly show it. I looked on line for good images of M110 as a reference and found that they are few and far between! I realised early on that I'd wandered into a yellow colour shift but never really got away from it. I was concentrating too much on stretching the limited data. I think that's where the noise has come from as I do always either with PHD2 I need a darker and clearer sky and more subs next time, it's certainly a worthwhile target. I only set out to image it because with my gear M31 would be a mosaic job and that's new territory for me and I'd struggle to get enough time on acquisition. Link to comment Share on other sites More sharing options...
symmetal Posted September 9, 2021 Share Posted September 9, 2021 Here's a crop of my M31 image showing M110 which may help. It's 60 mins each of RG and B and 90 mins of L under Bortle 3 skies. I don't know if the blue centre is actually from the galaxy itself or the star which happens to be in line with it. Your image has captured the two darker regions around the centre well. Alan 2 Link to comment Share on other sites More sharing options...
Paul M Posted September 9, 2021 Author Share Posted September 9, 2021 1 hour ago, symmetal said: Here's a crop of my M31 Very nice, and that wasn't even your primary target! And, wow, don't it just highlight the awful colour of mine! I'm minded to have another go at my data but to be fair I'm limited by the lack thereof! 1 Link to comment Share on other sites More sharing options...
ONIKKINEN Posted September 9, 2021 Share Posted September 9, 2021 1 hour ago, symmetal said: I don't know if the blue centre is actually from the galaxy itself or the star which happens to be in line with it. Your image has captured the two darker regions around the centre well. From Wikipedia: This galaxy has a morphological classification of pec dE5, indicating a dwarf elliptical galaxy with a flattening of 50%. It is designated peculiar (pec) due to patches of dust and young blue stars near its center. Huh, i actually always thought seeing blue in M110 was just artistic vision from processing. I always thought that something went wrong in colour balancing when i saw blue from an elliptical galaxy. You learn something new every day i guess. 2 Link to comment Share on other sites More sharing options...
vlaiv Posted September 9, 2021 Share Posted September 9, 2021 23 minutes ago, Paul M said: I'm minded to have another go at my data but to be fair I'm limited by the lack thereof! For start - maybe consider binning your data to actual resolution achieved? The way it is - it is very over sampled: You can easily bin that by x4 to improve SNR x4. 1 Link to comment Share on other sites More sharing options...
peter shah Posted September 9, 2021 Share Posted September 9, 2021 unusual to see this as a main featured image...great to see. 1 Link to comment Share on other sites More sharing options...
symmetal Posted September 9, 2021 Share Posted September 9, 2021 19 minutes ago, ONIKKINEN said: From Wikipedia: This galaxy has a morphological classification of pec dE5, indicating a dwarf elliptical galaxy with a flattening of 50%. It is designated peculiar (pec) due to patches of dust and young blue stars near its center. Huh, i actually always thought seeing blue in M110 was just artistic vision from processing. I always thought that something went wrong in colour balancing when i saw blue from an elliptical galaxy. You learn something new every day i guess. Good to know it's real from the galaxy, and that Startools or Photoshop wasn't taking liberties. 😊 Alan 1 Link to comment Share on other sites More sharing options...
Paul M Posted September 9, 2021 Author Share Posted September 9, 2021 1 hour ago, vlaiv said: For start - maybe consider binning your data to actual resolution achieved? The way it is - it is very over sampled: You can easily bin that by x4 to improve SNR x4. I agree! This was only the second outing for this camera. On it's first outing I binned 2x2 . The sky conditions played a big roll but the binned data just seemed more compliant to my intentions in processing. I'll batch bin the M101 data and reprocess it. Would make an interesting comparison. The other variable being my "workflow". I don't have any strict system. No chance of processing the same data the same way! Link to comment Share on other sites More sharing options...
Paul M Posted September 9, 2021 Author Share Posted September 9, 2021 Here it is with the same data batch binned 3x3 by ASTAP. I re stacked in DSS again and stretch/curves in P.S. but it was washed out, no colour. So I did it all in ASTAP. Seems to have done a better job but still no colour. Anyway, as a proof of concept it's shows that I can safely bib 3x3 with little, if any, loss of definition (not that I doubted you @vlaiv ) Still noisy because it is stretched to the limit to get anything worth looking at! 1 Link to comment Share on other sites More sharing options...
symmetal Posted September 9, 2021 Share Posted September 9, 2021 2 hours ago, Paul M said: Here it is with the same data batch binned 3x3 by ASTAP. I re stacked in DSS again and stretch/curves in P.S. but it was washed out, no colour. So I did it all in ASTAP. Seems to have done a better job but still no colour. Anyway, as a proof of concept it's shows that I can safely bib 3x3 with little, if any, loss of definition (not that I doubted you @vlaiv ) Still noisy because it is stretched to the limit to get anything worth looking at! Much better on the noise front. If you want to post your stacked image, I could see what Startools can do to get some colour. 🙂 Alan 2 Link to comment Share on other sites More sharing options...
vlaiv Posted September 10, 2021 Share Posted September 10, 2021 11 hours ago, Paul M said: Here it is with the same data batch binned 3x3 by ASTAP. If you have original linear version (one from first post) - maybe post that as well as it is easier to bin single image in the end. 1 Link to comment Share on other sites More sharing options...
Paul M Posted September 10, 2021 Author Share Posted September 10, 2021 *Large File Alert* Ok, here is the original bin 1x1 stack ( I always save DSS stacks as TIF for direct export to P.S.) Autosave.tif And this is the bin 3x3 stack (stacked in ASTAP): M110, 2021-09-07, 20x240L, EQMOD HEQ56, ZWO ASI071MC Pro_stacked.fits You'll see that the flats didn't cure the vignetting.... Must try harder next time. It's the post processing to cure that that is killing the whole thing in this instance. 1 Link to comment Share on other sites More sharing options...
vlaiv Posted September 10, 2021 Share Posted September 10, 2021 Here is bin x4 of original stack. I did not remove vignetting, and cropped to try to minimize it - but once I stretched - it really shows. However, image is quite smooth now (I did some selective denoising) and there is a lot of structure in the galaxy: 1 Link to comment Share on other sites More sharing options...
symmetal Posted September 10, 2021 Share Posted September 10, 2021 Hi Paul, Here's my efforts with Startools. I did a 3x3 and 4x4 bin version to compare. Startools 'Wipe' module did a pretty good job with the vignetting, better on the 4x4 bin version. I managed to reveal the blue centre of the galaxy and some of the stars show some colour too. 😊 Side by side the galaxy colour is a bit green on the 3x3 version. 🙂 Binned 4x4 Binned 3 x 3 Alan 1 Link to comment Share on other sites More sharing options...
Paul M Posted September 10, 2021 Author Share Posted September 10, 2021 And the winner is.... Me! 🤣 No, seriously guys. Thanks for spending time on my image. I was a bit unexcited about the original image but having seen the potential in my shallow data I'm inspired to go back to this object very soon and start afresh. A darker site and better flats would be a start. 1 Link to comment Share on other sites More sharing options...
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