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johneta

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About johneta

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    Nebula
  1. Thanks for the suggestion of pics Blue Straggler. I have now spent an embarrassing number of hours on stacking these images and trying different options. To cut a long story short.. My original problem of not being able to take Autosave straight to PS doesn't seem to be too much of an issue now. I found that once I started to really stretch and add saturation to the image that some bad posturizing started appearing and I could not get rid of it so any further editing of image was pointless But I stumbled across a weird issue in my PS. At a certain zoom level (Wider View) while I was editing the posturizing was visible BUT then when I zoomed in just one more click the posturizing dissapeared. This made me think of saving the image as a 16 bit tiff file at this stage and see what happened. When I saved the image it had NO posturizing and was clean and smooth. So the Weird artifact is added by PS just at certain zoom positions but is never visible in the saved image. A workaround would be to save the image early on in the editing phase and reopening it (16bit Tif). Then it edits as if its a normal image. It may be a bug/quirk of PS when you convert the image from 32bit (from DSS) to 16 bit when you first bring it into PS ?? So anyway now I find that editing an Autosave and an adjusted DSS image with settings embedded, give about the same outcome when adjusting in PS. Bringing a AutosaveFits DSS image into Fits Liberator and then bring the R,G,B images into PS and combining them into an RGB image is similar but for me slightly worse (I did struggle getting good contrast in Fits Liberator when I stretched mages though) So all in all I can now not see much difference in the 3 different methods. Although I would pick this one --Do very basic adjustments in DSS, save as a 16bit tif with adjustments embedded and used, and then edit in PS. It can be very hard to do comparisons sometimes due to the time it takes to stack and edit. You can get pretty lost in the middle of it all. Thanks for the suggestions. Here's the images I was talking about. Its of a Dark nebula close to the southern cross pointers (I'm in New Zealand). I found it a pretty hard subject as its quite dim and hard to pluck out detail in amongst the sky glow. I use an Orion 8" F4 Newt but I haven't got a coma corrector yet so please excuse the nasty stretched stars away from center. Camera is Canon 1200d(Rebel T5) unmodded. Image is about 1hr 40mins of lights total (Dithered). No darks, No Flats, No Bias Image 1. 1 x light image unaltered (of the 24 or so). Image 2. Stacked in DSS, Basic adjustments made and embedded and used in saved image, then edited in PS (1st FAVORITE) Image 3. Stacked in DSS, Autosave saved in Fits format, Autosave brought to FitsLiberator, FL opens it as 3 separate R,G,B greyscale images then you stretch them there and save each one as a 16bit tiff,then bring into RGB channels of a PS image and combine them to create an RGB image. Then just normal PS editing. (3RD FAVORITE AS I HAD ISSUES GETTING GOOD CONTRAST ON SEPARATE RGB IMAGES-I COULD PROBABLY DONE BETTER WITH MORE PRACTICE ON THIS ONE) Image 4. Stacked in DSS, Autosave saved in 32bitTif format, Brought into PS, converted to 16bit with Gamma and exposure setting, then edited in PS as usual. (2ND FAVORITE - THIS SEEMED ESSENTIALLY THE SAME AS IMAGE 1 BUT I DIDN'T FINISH IT OFF VERY WELL AS I WAS GETTING SICK OF IT AT THAT STAGE. IF I WAS FRESH I THINK IT WOULD HAVE NETTED THE SAME RESULT AS IMAGE 2) Image 5. This is a screenshot of image 4 showing the posturizing I mentioned. As I said this weirdly dissapeared when I either zoomed in a bit or saved it as a jpg or tiff
  2. Hey thanks alot. That really is a missing piece of information. I haven't seen anyone else mention that. Makes a lot of sense. I had a play and did it a similar way that you described and yes it works well !! Yes it is horrible to use but you only have to do a few things on it and your done I guess. I've got the methodology sorted now so I will practice it and it looks like it will give good results. It really surprises me that so many others don't seem to know about this, but it seems like a crucial step. Thanks Again
  3. MM interesting. 'save as three RGB 16bit files for PS' -- are you doing RGB seperate captures?? I use DSLR at the moment, could I do the same but save as a single 16bit file for PS.
  4. Thanks Bright Giant I did catch a setting or 2 in DSS that was helpful, so thanks for that. Most important was dont tick "set the black point to zero" in 'RAW/FITS DDP settings' or you can get a very dark image that no amount of stretching will fix. I restacked an image over and over again with different DSS settings and bringing over to PS with or without settings embedded in the 16bit tiff, but the best image is always with basic settings done in DSS and embedded in the image. Im disagreeing with the majority on the net (hence my frustration) but its the only way I can get the better image. Thanks again
  5. Thanks Blue Straggler I have tried this again. I restacked an image over and over again with all sorts of settings in DSS and brought them over to PS, with or without settings, and I still think its better to do basic adjustments in DSS and embed the settings in the 16bit Tiff image. I know Im disagreeing with most suggestions on the net (hence my frustration) but its the only way I can get the better image. Thanks again
  6. Another update Alan. I found a "set the black point to zero" tick box in DSS 'RAW/FITS DDP settings' was ticked. If you have this ticked and dont take care adjusting histogram in DSS it can create a very dark image that no amount of stretching will fix. I think it should always be unticked. I also went back and re stacked an image over and over with different settings and taking it to Photoshop with or without embedded adjustments, and I agree with you it is always better to embed the adjustments -- being careful to do them subtely in DSS first. Thanks again
  7. Thanks. When you say 'save a 16bit tif with embedded settings, it should be dark' Do you mean do some adjustments and then save or just save with no adjustments
  8. This is an old post I know, but I disagree with the 'dont adjust in DSS but rather bring across to PS and do the stretching etc there'. ---I cant get this to work. I have to stretch it so much that the image gets very noisy and ugly. Also when I try to add saturation to the monochrome looking image, I just get an overall hue to the image-- no individual colors. I'd love to hear a possible thing Im doing wrong as I can only get it to work if I stretch/saturate in DSS but then DSS is noisy and adds artifacts. Note: I have recently tried trial versions of APP and Pixinsight and easily got noise free bright images with plenty of color. Help Please. Thanks JD
  9. Hi stonedunicorn I have the same issue as you (although I have around 2-5 min exposures). When I bring the DSS stacked image to Photoshop it is dark and monochrome looking. I have to stretch it a huge amount and it gets very noisy and ugly. I try to add saturation, but as it looks monochrome all I get is an overall increased hue to the whole image--no individual colors. I have seen many people on the net say to not adjust curves/saturation in DSS which makes sense, but it never works for me. The only way I can get it to work is to adjust curves/Saturation in DSS and then bring over to Photoshop. But DSS is not great for that and introduces noise and artifacts to the image. So I cant understand how many people make it sound so easy. If you have got an answer to this issue please post it here as I would love to know. Also note I have recently tried trial versions of APP and Pixinsight and was able to easily get good brightness without noise, and good color in my images. Thanks JD
  10. Thanks Alan. Same for me, but I still feel results aren't that good and I was hoping for better the other way. I also recently tried Trial versions of APP and Pixinsight and was able to get significantly better results quite quickly (not withstanding steep learning curve) Cant afford that at the moment though. Also note, I can get better results by stacking manually in Photoshop. I get very smooth noise free background with virtually no noise and no odd artifacts. John
  11. I have been using DSS for a couple of years now and have never really been happy with it. I do the stack and end up with the mostly monochrome image that seems normal for DSS. Also the auto brightness settings on the stacked image are usually way over stretched. Both these issues are easily fixed with the controls in DSS. (for the preview image) I have been saving the image with these settings embedded, and opening it in photoshop. I can get OK-ish results but DSS seems to have lots of artifacts and is quite noisy. People on the net say not to use the saturation or level controls in DSS but to do all that editing in Photshop (or similar). Just save the the unstretched, un-saturated image, and use that. Sounds like a good idea, but I have never been able to get that to work. The image is very dark, and any amount of stretching required is huge, and gets very noisy and horrible looking. Also the image looks monochrome to me, and when I try to saturate the image all I really get is an overall colour hue to the image. No individual colours in different parts of the nebula as are actually there in the original subs. People who recommend taking the unstretched/un-saturated DSS image into photoshop seem to have no problems getting good results. Am I missing something very simple? Sorry for long winded question. Thanks for any help. I am shooting with a Canon DSLR 1200D(Rebel T5)
  12. Thanks guys. I havnt seen that before. I will have a good read and begin work on a conversion I think. Looks very good
  13. I want to fix the backlash (particularly Dec) on my Non-GoTo Starwatcher EQ5 You can adjust the mechanical backlash quite well on the eq5. BUT the motors themselves have a few seconds of backlash!! If you unscrew the motor and run it by itself. -Now set the rate to 2x on the hand controller so the motor is running slow but you can still see it moving. hit the left button on the dec motor and watch the cog move. Now hit the right button on the controller - you will see that the cog does not begin to move in the opposite direction for 2-3 seconds !! In that period of no movement, you can hear the motor is turning, but there is no movement of the shaft itself for 2-3 seconds. So there is a large amount of backlash in the internal gears of the motor itself. I have just discovered this. Im thinking of looking for some replacement motors. Anyone found a solution for this?? Thanks
  14. You can adjust the mechanical backlash quite well on the eq5. BUT the motors themselves have a few seconds of backlash!! If you unscrew the motor and run it by itself. Now set the rate to 2x on the hand controller so the motor is running slow but you can still see it moving. hit the left button on the dec motor and watch the cog move. Now hit the right button on the controller - you will see that the cog does not begin to move in the opposite direction for 2-3 seconds !! So there is a large amount of backlash in the internal gears of the motor itself. I have just discovered this myself. Im thinking of looking for some replacement motors. Anyone found a solution for this??
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