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geoflewis last won the day on March 20 2016

geoflewis had the most liked content!

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About geoflewis

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  1. Well done Chris, that is far from being the very, very, very poor image that you called it. Trust me, this is a difficult target from the UK, especially when you have roof tops, no astro dark and street lighting to contend with. I think that you got a lot right here, your stars are pretty round, so guiding must have been reasonable with 5m subs. The stars also show some colour, with good separation in several of those close pairings throughout the image and the 'pillars' in the nebula are clearly seen, so as you say, it is unmistakably M16. I tried this target a couple of times from my previous home in light polluted Surrey, with decidedly mixed results and even from my now much darker Norfolk skies with a cooled mono CCD and C14 it's a real challenge, even after integrating 3.5 hours LRGB data.... (see https://www.astrobin.com/stqw75/ if interested). I know that you will get a much better version in future, but I still think that this is a more than fair starting image, poor compared to what you wanted maybe, but IMHO it is not triple 'very' poor
  2. Goodnight Chris - nice Moonshot
  3. Goodnight Gina. I'm heading that way soon. I have about 15 minutes of darks left to capture then I'll be shutting down the obs and heading to bed for some much needed sleep.
  4. I should think so too Gina, I'm out of breath keeping up with you - you rock. I'm looking forward to seeing the final images.
  5. Thanks Ray, that would be great.
  6. I could do with some of that. It rained here earlier, but if I wanted to I could have counted the spots on the patio - well actually not, as they dried almost as soon as they fell....
  7. Thanks Carole, From what I can see, the main problem in my imaging train is there is slop in the draw tube of the TSAPO OTA itself when it is fully, or nearly fully extended, which it is with my new QSI adapters. I've got a couple of extension tubes, but the long one (I think 80mm) takes the camera beyond the required back focus and the shorter 35mm one gets focus ok, but only with most of the OTA focus tube extended. I probably need an extension tube in the 50mm-60mm range to minimise the slop in the OTA's assembly. There's always something to fix....
  8. Correct, darks and bias won't know that there is a filter there. You may get away without new flats, but I'd shoot new ones as they're quick to capture.
  9. Thanks Ray, I can do that, however, there are lots of stars in the NAN region, so can I use those raw sub images? Also do you have any documented source (idiots guide for me that is) on how to interpret the data and then use that to 'fix' the source of any problems identified?
  10. Thanks for this, especially the way you've presented zoomed crops of the various regions of the image. I do have a copy of CCDI, which was a shared purchase a couple of years with another imager who actually purchased it (so maybe semi pirate ), but I don't understand what I'm looking at when I run the files through it, just lots of weird patterns and no instruction manual to explain them - I don't even know if one exists. Guiding was pretty good, not the best, averaging at 0.74" total RMS (RA=0.54",Dec= 0.50") whilst imaging at 1.92"/px, so should be good enough, but PHD Log Viewer reported that my PA was poor at 10', so I need to look at that. I didn't run any deconvolution, so I could try that, but that won't fix the elongation, or will it?
  11. I had another go a processing my NAN Ha data as a mono image, so hopefully it's an improvement, to me it's softer with more subtle detail in the main body of the nebula and less harsh edges in the gulf of Mexico region, but what do you all think please? The main processing changes were using DDP instead of ArcSinH for the main stretch, as I got finer control, plus I backed off the high pass filter and raised the black point to make the transitions more subdued. In doing that, I looked more closely at the star shapes and see that they are distorted particularly in the corners, especially bottom left and top right, but that the direction of elongation changes as you pass through the image. I'm pretty useless at diagnosing the cause of these issues, but am thinking that it might be a tilted sensor, perhaps due to sag in the focus rack of the TSAPO. I replaced the connectors between the camera and OTA so that I can use the same QSI mounting plate for both my C!4+Optec lens and the TSAPO, but I now need to rack the TSAPO draw tube out much further than previously and I noticed that there is more play / sag. If anyone with more experience in these matters would like to offer an opinion and/or advice that would be great please. TIA
  12. That looks great John. I can't comment on the colour palette as I know zip about processing NB data other than Ha in mono (I know very little about that too) and Ha added to RGB, which is still a challenge for me....
  13. It's excellent Carole, it looks like that lens got all of it very well framed
  14. Hi Steve, I think I'm in the same boat. Self taught on processing, followed lots of videos, tutorials, etc. and have some 'recipes' that seem to work on some images, but I can quickly get out of my comfort zone as I found when trying to process my mono Ha NAN image recently - really was just making things up on the fly until I got to 'well that will have to do...'
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