gorann Posted October 8, 2018 Share Posted October 8, 2018 4 minutes ago, Rodd said: No worries--join teh club. I am always amazed at how different the image looks without stars--almost like its blurry, even though none of the details are different. I think the stars add a sense of depth. For me anyway, images look clearer and sharper with stars. I like your version though. It certainly eliminates any star troubles. Rodd Yes, I agree, it looks fuzzier even if it is not, so when I first now saw it without stars I though it may need some sharpening. But, on the other hand I guess gas and dust clouds can be allowed to be fuzzier than stars. Link to comment Share on other sites More sharing options...
Rodd Posted October 8, 2018 Author Share Posted October 8, 2018 13 minutes ago, gorann said: But, on the other hand I guess gas and dust clouds can be allowed to be fuzzier than stars. Well--it is a nebula despite the beautiful structure Ha provides. Oversharpening has always been a pitfall of mine. Rodd Link to comment Share on other sites More sharing options...
Rodd Posted October 8, 2018 Author Share Posted October 8, 2018 23 hours ago, wimvb said: Excellent image of my favourite part of the Heart nebula. Great reprocess as well. However, I do like the smoothness of the original. Normally I like images with a tiny amount of noise left. But for this, I quite like the "smooth shave" of the original version. I fixed it 14 hours ago, gorann said: I had not noticed the red dots but now I can see them. But that requires looking at the image at full resolution (and missing the big picture). In the old version they are small white stars so if you really want to fix them I assume you could just copy the stars from the old version and paste into the new. I often step back to older versions and retrieve selected things (like stars) when I find that something has gone a bit wrong. Easy to do in PS at least. By the way, this image would be interesting to see in a starless-version. Something to keep you occupied when you have run out of data........ OK--I went to some lengths to fix it. I reduced red, then I extracted the red channel--cleaned it up using noise reduction--but I first extracted the lum so I could reinsert later. I sharpened up the lum before inserting to avoid the smears. Then, because it was clean, I added some red back to the palette. Did it work? Just for kicks I cropped my heart taken at a focal length of 318 to compare with this one taken at 1,000. I find it amazing--a pixel scale of 1.1 vs 2.46. I suppose I shouldn't be too surprised by the 106--it is a Tak after all. FSQ 106 with .6x reducer (focal length 318)--way cropped! Link to comment Share on other sites More sharing options...
gorann Posted October 9, 2018 Share Posted October 9, 2018 Yes, you got some amazing detail in the Tak image. I expect you were very lucky with a clean and steady atmosphere those nights (even if you have light pollution). Probably also good guiding on the nice mount you have. What is your usual RMS? Link to comment Share on other sites More sharing options...
Rodd Posted October 9, 2018 Author Share Posted October 9, 2018 2 hours ago, gorann said: Yes, you got some amazing detail in the Tak image. I expect you were very lucky with a clean and steady atmosphere those nights (even if you have light pollution). Probably also good guiding on the nice mount you have. What is your usual RMS? To be honest--they are both TAK images--the upper is the TOA 130 and the lower is the FSQ 106 reduced. The cameras were different--the top with the stt-8300 and the bottom with the asi 1600. I thought the problem with the top image was too much noise control--but when I integrate the stacks, it looks like that right from the start. Focus could have been off--but based on the stars I don't think so, they are smaller in the TOA image which is to be expected. My RMS errors are typically .01 to .15 with the small scope. The TOA's RMS errors are typically .1 to .19 (I get nervous if they rise above .2). Don't think it was guiding, as other images came out fine with the TOA from the same time period. Maybe more data in the OIII and SII. Maybe conditions were bad--I really can't recall. One thing is for certain.....I need to revisit this target with the TOA Rodd Link to comment Share on other sites More sharing options...
gorann Posted October 9, 2018 Share Posted October 9, 2018 If your RMS values are in arsecs/pixel then that is exceptionally good guiding. Almost too good to be true. I expect that any value under 0.5 "/pix with your scope and camera is overkill. Maybe you use another unit for the RMS? Link to comment Share on other sites More sharing options...
Rodd Posted October 9, 2018 Author Share Posted October 9, 2018 8 minutes ago, gorann said: If your RMS values are in arsecs/pixel then that is exceptionally good guiding. Almost too good to be true. I expect that any value under 0.5 "/pix with your scope and camera is overkill. Maybe you use another unit for the RMS? If I have Maxim set to display pixels then: for my lodestar2 with 8.2um pixels and a FL of 261mm--the resolution is about 6.47 arsec/pix. So an rms error of .1 pixel would be about .6arcsec. The asi 1600 and the FSQ 106 at F3 shoot at a resolution of 2.46 arcsec/pix. So .6 arcsec is about 1/4th the resolution. I know that does not seem that great--but the stars are awfully small in the FSQ 106 images. For the TOA 130 at F7.7--which the lodestar2 and guidescope worked well for (after a brief period of doubt), the numbers are 6.47 for the lodestar and 1.1 for the TOA. Guiding is about the same if I balance the system well, as the weight is well under the capacity of the mount. The first setup I used the guidescope and lodestar2 on was the TOA at F7.7 just to verify that it would work at a focal length of 1,000. the consensus among the vendors that I was working with at teh time was that it was working fine. But I can't remember if I have it set to pixels or arcsec. But I am no expert on the numbers. I don't think I have a guiding issue on any of my scopes (I don't use the guidescope and lodestar2 on the C11Edge). My FWHM values are never as good as I would like--but the images look fine with respect to star sizes. Then again, at 2.46 arcsec/pix a FWHM value of 3.5 means that 80% of teh stars energy is contained in about 1.4 pixels--which is way less than 2 and 3 is the magic number according to.....to.....to....I can't remember the name but I know you know it. The tiny stars look like little crosses, so guiding has to be OK, and the wee bit bigger stars are square--so they are definitely undersampled. So I can go to 4.0 arcsec.pixel with FWHM and see virtually no difference in stars unless I zoom to 4 or 5 to 1. Even 4.5 is still less than 2 pixels. This is my take anyway--maybe way off base. But whether I have it set at pixels or arcsec, the numbers come out about the same. You divide the guiding resolution into the imaging resolution. Whether you use .1 arcsec or .1 pixel than convert to arcsec is about the same. For the TOA at 1.1 acrsec per pixel it is the same. Anyway--When I get home I will check to see what I have it set at Rodd Link to comment Share on other sites More sharing options...
gorann Posted October 9, 2018 Share Posted October 9, 2018 Well, it sounds like you have sufficient guiding and all under control. Lucky man! Link to comment Share on other sites More sharing options...
Rodd Posted October 9, 2018 Author Share Posted October 9, 2018 5 minutes ago, gorann said: Well, it sounds like you have sufficient guiding and all under control. Lucky man! Not so sure--the TOA at F7.7 and the asi1600 images have been.....a bit underwhelming. the above comparison is quite marked. The M106 took an awful lot of work and the details are not as sharp as expected. maybe the guiding is off a bit and it is showing up as images that are not quite as sharp as they should be. I thought it had to do with F7.7 being slow and needing more data. But you have me thinking...........Nyquist is the name. On the tip of my tongue. Rodd Link to comment Share on other sites More sharing options...
RichLD Posted October 9, 2018 Share Posted October 9, 2018 Superb images once again, well done Rodd! Link to comment Share on other sites More sharing options...
Rodd Posted October 9, 2018 Author Share Posted October 9, 2018 6 minutes ago, RichLD said: Superb images once again, well done Rodd! Thanks Rich Rodd Link to comment Share on other sites More sharing options...
Rodd Posted October 9, 2018 Author Share Posted October 9, 2018 27 minutes ago, gorann said: Well, it sounds like you have sufficient guiding and all under control. Lucky man! Wait a minute--forget it--I shot the TOA image with the STT-8300, with the self guiding filter wheel--an OAG like thing. So it can't be the guiding! And teh mystery deepens. Still though--I question my guiding with teh TOA at 1,000mm with teh guidescope. Craig Stark says not to exceed 4:1 and I am at about 4.7:1. Picky I know--but the devil is in the details in this business (a nasty, fire-breathing devil, the king of teh gremlins). Rodd Link to comment Share on other sites More sharing options...
glowingturnip Posted October 10, 2018 Share Posted October 10, 2018 ooh that's nice. I've got nearly the same shot, but in Ha monochrome only, I see I shall have to add O and S to it now. New version for me, the blue looks a little too 'disco' for my eyes in the old one. Link to comment Share on other sites More sharing options...
Rodd Posted October 10, 2018 Author Share Posted October 10, 2018 4 hours ago, glowingturnip said: ooh that's nice. I've got nearly the same shot, but in Ha monochrome only, I see I shall have to add O and S to it now. New version for me, the blue looks a little too 'disco' for my eyes in the old one. Thanks Stuart. I agree. But I think I want to attack this one again as well and get more data. Rodd Link to comment Share on other sites More sharing options...
Jkulin Posted October 11, 2018 Share Posted October 11, 2018 Simply Stunning Rodd, absolutely amazing. Link to comment Share on other sites More sharing options...
carastro Posted October 11, 2018 Share Posted October 11, 2018 Absolutely stunning. I prefer the brighter version. Carole Link to comment Share on other sites More sharing options...
Rodd Posted October 11, 2018 Author Share Posted October 11, 2018 2 hours ago, Jkulin said: Simply Stunning Rodd, absolutely amazing. Thanks John! Rodd Link to comment Share on other sites More sharing options...
Rodd Posted October 11, 2018 Author Share Posted October 11, 2018 2 hours ago, carastro said: Absolutely stunning. I prefer the brighter version. Carole Thanks Carole. The resolution does seem higher despite the greater pixel scale.. Rodd Link to comment Share on other sites More sharing options...
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