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DaveS last won the day on October 6

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    Bride Valley, West Dorset

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  1. Do you have a link? Google didn't turn up anything. Unfortunately I would be looking at a filter for a 135 format sensor with 43mm diagonal for which 2" mounted is marginal at best. Really need 50mm unmounted to be safe. Edit: Never mind, found it
  2. Sunday, I started a late run on Pickering's Triangle, 4 hours [SII] in 15 min subs but 2 1/2 hours in the wind triggered the weather monitor shutting everything down, except Sequence tried to carry on the run pushing the OTA into the roof which had closed. I still have no idea why. Didn't do anything yesterday, as I thought it was going to be clouded out, turned out to be clear. Bother. Tonight MO said cloud, but CO and good To Stargaze both said clear until at least 11 o/c so did another 4 hour [SII] run which completed without incident. Camera is warmed up and everything shut down for the night.
  3. This DaveS has an old Rosette as his avatar, the same as on another forum.
  4. I think I may have another look at things, but am unlikely to post an image until or unless I have something radically better. I have one or two ideas but don't know how they will pan out.
  5. Yep, this is why I'm hitting all around the bullseye. The rings in the first image are a combination of the deconvolution and the high pass filtering in the DDP routine that reveals more detail in the core of NGC 7331. Removing the stars and working on them separately would be logical, but I'm not sure what effect the diffraction spikes would have.
  6. I had another play with the data, applying a star erosion filter to the coregistered RGB channels before anything else, and taking greater care over the processing. I had to pull some of the sliders down to more gentle levels which has meant that I haven't been able to pull out all the detail in the core of NGC 7331 or else I would be back with dodgy stars again. I did pull the level of green down using a new "Attenuate Single Colour" tool in AstroArt 8 And now I think I will leave it alone.
  7. I managed to capture some more data on this, so now 30 subs each R, G, B (In G2v calibration) totalling 18 hr 45 min and 72 subs Luminance totalling 12 hr. not sure at the moment how much ended up in the final stacks as I had AstroArt reject subs with elongated stars, fuzzy stars (High FWHM) or high sky background. The Luminance stack was cropped to remove alignment edges followed by Gradient Removal and DDP with a "soft" High Pass" setting and Richardson Lucy Deconvolution. The RGB stacks were brought into the Trichromy process and aligned before being cropped and the RGB channels separated for gradient reduction. Again a "soft" High Pass DDP was applied followed by Richardson Lucy deconvolution. Close attention was applied to the histograms during this. The individual RGB stacks were now brought back into Trichromy before being Coregistered with the Luminance. Several rounds of Histogram Stretch followed to bring the range back to 16 bit before Colour Curves were applied to bring out the Core / Arms difference. There was an Unsharp Mask in there somewhere and a final Histogram Stretch just to bring up the background a touch. Phew! And I'm still not happy. There are some dark halos that are proving troublesome while still enhancing the detail. C&C welcome, together with any suggestions as to how to proceed from here.
  8. Didn't get much further after my post as cloud came over and the safety monitor shut everything down. Ah well. Goodnight all.
  9. Currently running another 6 hour Luminance on Deer Lick / Stephan's Quintet. Although the first sequence last night completed without problems for reasons that still escape me the second borked with Autoslew reporting servo errors. A look in the log showed an undervoltage which is puzzling.
  10. Fingers crossed for tonight. Running two targets, Deer Lick / Stephan's Quintet 9 subs in G2v calibration, then 3 hours on the Flame Nebula to finish off. Should finish some time after 5.30 next morning.
  11. Yup, you can tell it's cloudy. Having updated AstroArt to version 8 I thought I'd try reprocessing some of my older data. This is M106 from last year with the ODK rig. I captured 13 hr 10 min Lum, 6 hr 30 min Red, 6 hr Green and 7 hr Blue in 10 min subs. Sigma stacked in AA8 with rejection set for elongated stars, poor background and high FWHM. The individual RGB stacks were given a Digital Development Process (Much improved from V7) followed by Trichromy. The Luminance in addition was given Richardson-Lucy deconvolution. After LRGB combination the composite frame was cropped to get rid of some severe alignment edges (The camera had rotated without my realising it) then gradient reduction applied. This was followed by all manner of colour adjustments involving saturation boosts and colour curve adjustments. Lastly a slight histogram stretch was applied to bring up the background to reveal lots of faint fuzzies. The flare just right of centre at the bottom is from light getting into the camera from the CCTV camera flood after meridian flip. I'm still not happy with this. If I continue then I'll combine the clean data from this set into a super-luminance and collect fresh RGB data with G2v calibration. Plus I really need a shed load of H-alpha as the 10 min subs I acquired were rubbish. Will probably need 1200 sec subs to get above the noise floor.
  12. Had another run at this, trying to pull the background up while not blowing out the core of NGC 7331 or over blowing the cores of the stars. Very difficult. Not sure if it's the raw data or my processing. I reckon more data is needed but have no ideas as to when I'll manage to capture it. I would really like to get more orange / yellow / red tones in the core.
  13. My current office PC is way out of date for Win 11 as it dates from 2011, and the CPU is an i7 2600. I'[ve been planning a new AMD Ryzen based tower for early next year for serious image processing. I doubt that my remote PCs will run Win 11 either as the CPUs are too weedy. Boo.
  14. Thanks Brian. Going to pause this for a day or two, hopefully come back to it with a fresh perspective. Could do with more data, possibly H-alpha to pop the HII regions in 7331.
  15. Stephan's Quintet and the Deer Lick group, NGC 7331 plus "fleas". This is the fourth LRGB iteration that I thought good enough to save, I've thrashed around many more that were total rubbish. 15 subs RGB in G2v calibration (R&G 600 sec, B 1050 sec) and 36 600 secc Luminance subs from the ODK rig. Best 90% stacked in DSS with full calibration, then tortured in AstroArt 8. Saved as a JPEG. If anyone has any ideas as how to proceed from here I'd be happy to know.
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