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x6gas

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x6gas last won the day on June 27

x6gas had the most liked content!

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About x6gas

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  1. x6gas

    SH2-132

    Ah yes... I was forgetting how big the FLI ML16200 chip is in comparison to the Atik 460/490 that I usually use. I very much enjoyed seeing this image Brendan so thanks, as ever, for sharing.
  2. x6gas

    SH2-132

    Another wonderful image Brendan. Is this a mosaic, I wonder? - I recall this being a pretty big target.
  3. Bit late to the party but just to add my appreciation of this terrific image, Ciarán. Loving Olly's mash up too - what a wonderful part of the sky... Great stuff...
  4. Nice image Bobby. On my monitor the background looks a bit black to me and I wonder if you've clipped the black point at some stage. Cheers, Ian
  5. Wowsers - what a surprise. Thanks so much - lots of great renditions and I am absolutely honoured. I agree with @Grant - this is a tough target to process. In honesty, I was never particularly happy with the results I got from my own data, but the IKO stacks were lovely to work with - especially the OIII which had so much to give - and I was really pleased with what came out of the process. There were so many great images posted in the thread... it must have been tough to judge! Thanks again FLO and IKO for providing this great data. I really enjoyed processing it and seeing all of the submissions.
  6. OK could you indulge me here Olly... by default I always get that posterized view of the background map (whether using ABE or DBE) but as I understand it that's just the Screen Transfer Function skimping on resources... So could I ask: if, in PI, you go to IMAGE > Screen Transfer Function > Use 24-bit STF LUTs (or indeed if you drop the STF into Histogram Transformation and apply the stretch for real) then do you still get the crude gradients? I am curious whatever, because I assume that you don't usually see backgrounds looking like this... so something must be different with this file. Ian
  7. So I don't think that this has anything to do with your capture (the individual sub and the stack itself are definitely not over saturated)... so in my view it's something to do with the CCD range that AstroArt is applying to the stack, for some reason.
  8. Well when I open that file in AA5, View>Range>CCD range gives the full monty, as I'd expect.
  9. Hmmm. This is an interesting one. I should say that I am stuck with AstroArt 5 so things may be different with more modern releases, but: If you click on View>Range>CCD range then you get the burnt out image that Dave posted originally. This is strange as whenever I've done this with my data it gives the complete CCD range (as you'd expect from the name of the function) but that's not the case here - you get a very different result if you select View>Range>Min->Max... so saving that gives this (which behaves OK when I stretch it in PS): 9 Hours O.tif so I wonder if AstroArt is somehow misreading or misinterpreting the bit depth of the camera? Ian
  10. And I would like to be third in line in the unlikely event that the other two sales fall through.
  11. Well once again thanks to the Ian King Observatory and to FLO for supplying really wonderful data - this data is incredible, in fact. It's great to have have such wonderful data as you can remind yourself of all sorts of techniques and tricks instead of spending the time wrestling the data to submission. I offer The Crescent Nebula three ways. For each version, I deconvolved the data in PI and applied a gentle dose of Multiscale Linear Transform Noise Reduction before moving to PhotoShop. I also used a starless version of the OIII (generated using Starnet ++) to give that channel a bit of a boost. Once in PI, there was a bit of sharpening using High Pass filter at various strengths but most of the "processing", such that was needed, was playing around with the relative strengths of each channel and some playing with selective colour. There are some absolutely brilliant renditions of this target on this thread. I've never been completely happy with the versions that I've produced using my own data but I like what I've done with this data much more. The first is a relatively straightforward bicolour version. This has an additional OIII layer of the nebula added to bring out the fainter stuff: And this was supposed to be a gentle SHO version, but it actually looks a bit racey to me now that I see here... and finally an SHO where I have pushed the Ha a bit harder: Thanks again IKO and FLO! Ian
  12. Ummmm. I think that @steppenwolf deserves all the credit. If I am honest I don't understand - at all - how on Earth a problem with the OAG caused your problem. If the OAG and guide camera are securely anchored I can't see how it was causing this trailing. But then, that's why Steve is the Scope Doctor
  13. Lovely image Peter. I have some narrowband and RGB data in the can for this object... I collected the RGB for star colour but I'm wishing I had more looking at this!
  14. Well I'm stumped too! It seems there is something very odd about this. If I look at the whole frame, the stars in the bottom left in @steppenwolf's mosaic seem OK if a little soft. I *think* I am correct in saying that if this was tilt, then the coma would be pointing away from that corner of the frame but in actual fact the trailing is perpendicular to it. I've analysed the corners and centre of the frame using PSFimage (a very useful PI script) and the results more or less confirm what the eye tells you... except it seems that the aberration is worst across the diagonal from top left to bottom right. I'd expect it to be worst in the top right if the star shapes are best in the lower left. Here are point spread functions arranged as they have been sampled from the image: I did wonder if this had something to do with a problem with your guide cam not being orthogonal to the camera, but (a) I've successfully guided with all manner of aberrations on the stars produced by my OAG and (b) your camera sensor is parallel to the pick off prism of your OAG so if that were the problem I'd expect the best stars to be in the centre of one side of the frame and not in one corner and (c) guiding problems would give the same problem across the whole frame (unless there is a second problem confounding things). Upshot: even though CCD inspector seems happy with the collimation, that's all that I can think of that would giving such odd results. I'd suggest a good old fashioned star test - look at a defocused star and see if the shadow of the secondary is bang in the middle. This is something that can easily be checked with an artificial star so at least you don't have to waste a clear night on it. All very frustrating, I'm sure!
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