ollypenrice Posted June 2, 2020 Share Posted June 2, 2020 This is a reprocess of old data using a star reduction technique I hadn't encountered at the time I did the original. Obviously we're in the thick of the Milky Way here and holding down the stars to let the nebulae do the talking is tricky. The image is HaLRGB from the Tak FSQ106N and full frame Atik 11000 (still my favourite camera...) Both nebulae were enhanced by applying higher resolution data from the TEC140. All I did was remove the stars entirely from a copy and then replace them with the originals at only partial opacity in blend mode lighten. Very easy indeed and, for the first time, I'm happy with this one. Mount, as ever, was a Mesu 200. Olly 27 Link to comment Share on other sites More sharing options...
ollypenrice Posted June 2, 2020 Author Share Posted June 2, 2020 By the way, Monique spotted a human face in this one. It's in profile, facing to the left. Find the closed eye above the Eagle's claw and you'll spot it. We called it 'The bearded face.' It would make a companion for the WItch Head. 😁lly 7 Link to comment Share on other sites More sharing options...
RayD Posted June 2, 2020 Share Posted June 2, 2020 Very, very nice indeed. Love the fact that the stars are perfectly controlled, but still an awful lot of them. Great spot with the face; very clear. Looks a little like a sleeping baby with a blanket/shawl wrapped around it. 1 Link to comment Share on other sites More sharing options...
old_eyes Posted June 2, 2020 Share Posted June 2, 2020 Very nice Olly. The whole thing has a brooding, slightly ominous feel to it. the star reduction technique is clever, and I will give that a try when I have the right target. 1 Link to comment Share on other sites More sharing options...
Annehouw Posted June 2, 2020 Share Posted June 2, 2020 (edited) Well done, Olly! What "very easy" star reduction technique did you use? I have tried virtually all of them (Content aware fill in PS, Straton, Starnet++, PI StarMask, PI MaskGen script) and all of them work to some extent, but none can handle my bright stars with diffraction spikes, so I need to use quite some opto-neuro feedback processing (also called painting ;-)). Most of the algorithms presume that stars are round and I read somewhere that Starnet++ has been trained on round star images only. In the back of my head, I am thinking of experimenting to convolve a starmask with an single star image of a nice spiky star to get a spiky starmask. OTOH, when you put stars back in, it does not have to be pixel perfect. Edited June 2, 2020 by Annehouw Link to comment Share on other sites More sharing options...
ollypenrice Posted June 2, 2020 Author Share Posted June 2, 2020 (edited) 2 hours ago, Annehouw said: Well done, Olly! What "very easy" star reduction technique did you use? I have tried virtually all of them (Content aware fill in PS, Straton, Starnet++, PI StarMask, PI MaskGen script) and all of them work to some extent, but none can handle my bright stars with diffraction spikes, so I need to use quite some opto-neuro feedback processing (also called painting ;-)). Most of the algorithms presume that stars are round and I read somewhere that Starnet++ has been trained on round star images only. In the back of my head, I am thinking of experimenting to convolve a starmask with an single star image of a nice spiky star to get a spiky starmask. OTOH, when you put stars back in, it does not have to be pixel perfect. Hi Anne. I first tried Straton but it made a mess, so I made a copy layer, used Noel's Actions to select brighter stars on the top, expanded and feathered, erased them, then ran the dust and scratches filter on the bottom layer. This meant I could see the effect of Dust and Scratches in real time. It wouldn't have been satisfactory as a de-starred standalone image but I wasn't wanting that anyway. When I then put the original on top in Blend Mode Lighten I could let the stars back in at an opacity I liked. They were a bit spikey-looking so I gave them a very slight Gaussian blur. I suspect that with diff spikes your only option would be the clone stamp. Olly Edited June 2, 2020 by ollypenrice 1 Link to comment Share on other sites More sharing options...
Allinthehead Posted June 2, 2020 Share Posted June 2, 2020 Very nice Olly. I also use pretty much the same technique with the stars. I remove them with Starnet then blend the original with the starless in blend mode lighten. I then paste the this version over the original adjusting the opacity to taste. Works well with diffraction spikes too. Link to comment Share on other sites More sharing options...
Xiga Posted June 3, 2020 Share Posted June 3, 2020 18 hours ago, ollypenrice said: This is a reprocess of old data using a star reduction technique I hadn't encountered at the time I did the original. Obviously we're in the thick of the Milky Way here and holding down the stars to let the nebulae do the talking is tricky. The image is HaLRGB from the Tak FSQ106N and full frame Atik 11000 (still my favourite camera...) Both nebulae were enhanced by applying higher resolution data from the TEC140. All I did was remove the stars entirely from a copy and then replace them with the originals at only partial opacity in blend mode lighten. Very easy indeed and, for the first time, I'm happy with this one. Mount, as ever, was a Mesu 200. Olly Very nice Olly. I love this area of the sky. Probably because i have trees stopping me from capturing it from home (we always want what we can't have, right? 😋 ) ps - Don't know if it's just my monitor, but is the sky background a little on the blue side? Link to comment Share on other sites More sharing options...
Xiga Posted June 3, 2020 Share Posted June 3, 2020 6 hours ago, Allinthehead said: Very nice Olly. I also use pretty much the same technique with the stars. I remove them with Starnet then blend the original with the starless in blend mode lighten. I then paste the this version over the original adjusting the opacity to taste. Works well with diffraction spikes too. Richard, can you elaborate on this a little please? So you layer on the 'with stars' image in blend mode lighten on top of the starless one. This adds back the stars at their original size. So do you do an adjustment to this layer as well? Such as a downwards Curve adjustment to reduce their size, or something else? And then do you flatten (or do a Stamp Visible, same thing) and then layer this back on top of the 'with stars' image, and then reduce the opacity gradually until any dark halos around the stars start to disappear. Is that the general idea? So far I have very limited experience in doing this myself, but up to now I've only ever added the stars back simply in a Blend Mode Lighten layer. It sounds like you do it in 2 stages. Is that right? Link to comment Share on other sites More sharing options...
ollypenrice Posted June 3, 2020 Author Share Posted June 3, 2020 (edited) 3 hours ago, Xiga said: Richard, can you elaborate on this a little please? So you layer on the 'with stars' image in blend mode lighten on top of the starless one. This adds back the stars at their original size. So do you do an adjustment to this layer as well? Such as a downwards Curve adjustment to reduce their size, or something else? And then do you flatten (or do a Stamp Visible, same thing) and then layer this back on top of the 'with stars' image, and then reduce the opacity gradually until any dark halos around the stars start to disappear. Is that the general idea? So far I have very limited experience in doing this myself, but up to now I've only ever added the stars back simply in a Blend Mode Lighten layer. It sounds like you do it in 2 stages. Is that right? No. In my case the top layer containing the stars is not added at full opacity in blend mode lighten. That's where the reduction comes from. The cores of the stars are their brightest parts so they are the first parts to appear in BM Lighten. At partial opacity they are the only parts to appear in the blended image, which is why they are smaller. Once flattened at the chosen opacity I might well paste this star-reduced new version over the original to check my judgement. If I've over done the reduction I can reduce the opacity of the reduced one over the original. I can also remove from the top layer any brighter stars which have been damaged by the reduction process. (A quick dab with the eraser takes care of it.) Olly Edit: I didn't do it this time but another bright idea might be to paste the RGB-only on top of the starless HaLRGB since the RGB stars will be smaller and have unadulterated colour, possibly more intense. Something to try next time! Edited June 3, 2020 by ollypenrice 1 Link to comment Share on other sites More sharing options...
ollypenrice Posted June 3, 2020 Author Share Posted June 3, 2020 4 hours ago, Xiga said: Very nice Olly. I love this area of the sky. Probably because i have trees stopping me from capturing it from home (we always want what we can't have, right? 😋 ) ps - Don't know if it's just my monitor, but is the sky background a little on the blue side? Good call, Ciaran. Thanks. I'd been playing around with the 'something odd' I could see in the background but hadn't twigged that it came from the blue channel. With the blue brought down the non-Ha dust has come up and there's a more natural interaction between the dust and the gas. I owe you a pint, Sir! Olly 1 Link to comment Share on other sites More sharing options...
andrew s Posted June 3, 2020 Share Posted June 3, 2020 3 hours ago, ollypenrice said: Good call, Ciaran. Thanks. I'd been playing around with the 'something odd' I could see in the background but hadn't twigged that it came from the blue channel. With the blue brought down the non-Ha dust has come up and there's a more natural interaction between the dust and the gas. I owe you a pint, Sir! Olly Looks like "the face" is blowing Ciaran a kiss in gratitude. Regards Andrew 1 Link to comment Share on other sites More sharing options...
carastro Posted June 3, 2020 Share Posted June 3, 2020 (edited) Lovely image Olly, I never realised quite how close to each other these nebulae are. I also struggle with star reduction Techniques, actions seem to mess up the Nebula, and star removal tools make a right mess. I have found the best method is the one I picked up from MartinB which I have done a video tutorial of. This works well on telescope images but I found doesn't work so well with my Samyang lens, so am trying to devise other methods ATM. This is the link if any-one is interested: Edited June 3, 2020 by carastro Link to comment Share on other sites More sharing options...
silentrunning Posted June 3, 2020 Share Posted June 3, 2020 Cracking image. Great vibrancy. Seems we are all working on star removal/reduction methods. Link to comment Share on other sites More sharing options...
ollypenrice Posted June 3, 2020 Author Share Posted June 3, 2020 2 minutes ago, silentrunning said: Cracking image. Great vibrancy. Seems we are all working on star removal/reduction methods. It's a big issue. Small stars give an image the 'big telescope' look. Olly 1 Link to comment Share on other sites More sharing options...
Xiga Posted June 3, 2020 Share Posted June 3, 2020 6 hours ago, ollypenrice said: No. In my case the top layer containing the stars is not added at full opacity in blend mode lighten. That's where the reduction comes from. The cores of the stars are their brightest parts so they are the first parts to appear in BM Lighten. At partial opacity they are the only parts to appear in the blended image, which is why they are smaller. Once flattened at the chosen opacity I might well paste this star-reduced new version over the original to check my judgement. If I've over done the reduction I can reduce the opacity of the reduced one over the original. I can also remove from the top layer any brighter stars which have been damaged by the reduction process. (A quick dab with the eraser takes care of it.) Olly Edit: I didn't do it this time but another bright idea might be to paste the RGB-only on top of the starless HaLRGB since the RGB stars will be smaller and have unadulterated colour, possibly more intense. Something to try next time! Thanks for clarifying Olly. I was trying to visualise this in my head, but had forgotten about the Lighten blend mode. It makes perfect sense now, thanks! 5 hours ago, ollypenrice said: Good call, Ciaran. Thanks. I'd been playing around with the 'something odd' I could see in the background but hadn't twigged that it came from the blue channel. With the blue brought down the non-Ha dust has come up and there's a more natural interaction between the dust and the gas. I owe you a pint, Sir! Olly That looks splendid now Sir. Mine's an IPA thanks 😋 2 hours ago, andrew s said: Looks like "the face" is blowing Ciaran a kiss in gratitude. Regards Andrew 🤣 Once you see it, it's hard to unsee! It really does resemble a face with a closed eyelid. And is that a nightcap he/she is wearing? 😄 2 Link to comment Share on other sites More sharing options...
silentrunning Posted June 3, 2020 Share Posted June 3, 2020 Since star processing seems to be the order of the day I have had a bash myself, see post... Link to comment Share on other sites More sharing options...
old_eyes Posted June 3, 2020 Share Posted June 3, 2020 12 hours ago, ollypenrice said: Good call, Ciaran. Thanks. I'd been playing around with the 'something odd' I could see in the background but hadn't twigged that it came from the blue channel. With the blue brought down the non-Ha dust has come up and there's a more natural interaction between the dust and the gas. I owe you a pint, Sir! Olly Even better! 1 Link to comment Share on other sites More sharing options...
Knight of Clear Skies Posted June 4, 2020 Share Posted June 4, 2020 Very impressive. My only concern is, will I ever be able to unsee the face and look at the nebula? Link to comment Share on other sites More sharing options...
ollypenrice Posted June 4, 2020 Author Share Posted June 4, 2020 1 hour ago, Knight of Clear Skies said: Very impressive. My only concern is, will I ever be able to unsee the face and look at the nebula? My concern as well. The eagle has vanished! I think the Swan, though, is the object most like its name at the EP, especially if you rotate the diagonal to get the water level. Olly Link to comment Share on other sites More sharing options...
MartinB Posted June 6, 2020 Share Posted June 6, 2020 Lovely image Olly. Lots of interesting stuff in the background. I think it is the face of an Egyptian Pharoah. I always wondered where they were transported to when they died. 1 Link to comment Share on other sites More sharing options...
Knight of Clear Skies Posted June 6, 2020 Share Posted June 6, 2020 55 minutes ago, MartinB said: I always wondered where they were transported to when they died. Museums if they were lucky, gout remedies if not. Link to comment Share on other sites More sharing options...
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