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About Rodd

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    Brown Dwarf
  • Birthday 16/08/62

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    Astrophotography, music, the wilderness
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  1. M33

    Great advice. I agree. I am left with the following. Seems pale. Getting there?. The green cast bothers me--but I can't seem to rectify it Ha areas seem pink too.
  2. M33

    Well--the end of a long road. I reshot the Blue channel last night. Only got 24 10 min subs instead of 30, and conditions were not as good--but I was able to keep the FWHM <3 at least. The new flats worked like a charm and the blue channel looked pretty good. Goodbye unseemly artifacts. In fact, the red, blue and green channels look great--better on their own than the completed image. I can't seem to get the color of the galaxy right. For the first time in a long time I have broadband data that is easy to work with and cont compromised by sky conditions (I had a very unusually clear, dark week). Yet I can't put it all together.
  3. M33

    Ahh...thanks. Rodd
  4. M33

    Pardon my ignorance but what is cc? I never take my camera off my scope. If I do--then I have to reshoot my flats (I can never reattach it at precisely the same orientation). SBIG makes a big deal about the micron precision of the self guiding filter wheel-how it can rotate filters to within a micron of the previous position. It is supposed to be good for ensuring accurate flats. Maybe its marketing hype. My filter wheel is sort of attached to the camera--the self guiding filter wheel (SBIG). There are really no openings or holes. Why could they not seal the filter wheel (ie make it water proof). The only glass required would be a very thin, transparent glass. My flatner has 6 elements, I don't think an inert piece of glass a tenth of a mm thick (or some such thickness--maybe thinner) would change the optical properties of the system (noticeably). Besides, the glass could be like a shutter that closes when the camera is not in use and opens when it is activated. I was surprised at how much detritus was inside the filter wheel. Rodd
  5. M33

    I shoty a few subs and there was another V shape someplace else! They are fibers (tiny ones on the filters). Wimwas right--a fiber, but on the filter--I cleaned the filter and there were loads of them. Olly was right as well--the fiber was there when I shot my subs, but when I shot my flats it had moved--hence the reason the flats were useless to remove it. Back up and running. Won't know until I calibrate my subs. Note to camera manufacturers....its not enough that the sensor is in a sealed chamber--the filters should be sealed and a vacuum applied when it is closed up and an inert gas inserted. There was all kind of dust and fibers all throughout the interior of the camera. Its olny a matter of time till something like this happened
  6. M33

    But that's what flats are for--no? Rodd
  7. M33

    Oh yeah--one of the V shapes that caused the trouble is not on the flats. Strange. Rodd
  8. M33

    Thanks Wim--probably could do it without redoing then huh? I will see if I get the same V shape in blue subs at least. Besides, M1 (my next project) doesn't rise until around midnight so. Have to do something! I will have a look over your suggestions and see if I can figure it out probably take me longer than redoing them I just hope I don't have some kind of permanent issue. Still confused as to what it could be. Rodd
  9. M33

    Last one lest I succumb to the marathon.....not going to happen. but this one resolves the core a bit. Should I redo the blues, or leave well enough alone and conquer some other target?
  10. M33

    Here is a blend between the last one and the new one with Ha. I think I like this one better.
  11. M33

    I was thinking the same thing. What ever it was stayed in place for the 7 hours or so that I was using the blue filter. I would like to know what ever it is (hopefully was) why won't flats remove it? and why didn't the flat remove the normal V shaped smudge on the blue subs--it almost made it worse. Look at the HaLRGB image above, and note the blue artifact is no longer next to the red/brown artifact created by the V. I had to clone stamp that out of the master flat (or clone stamp it in actually). I hope I don't have a problem with something! Rodd
  12. M33

    Definitely strange. I was able to fix the flat not removing the normal smudge V from the blue channel (clone stamped it out on the master flat--seemed to work). But the wider V that is only on the blue subs can't be removed at all. The only thing I know that flats won't remove is dew or frost issues. Since its only on blue subs I don't think its that. I tried using different flats--but none fixed it--and they created other issues.Don't know. I am contemplating redoing the blues tonight. Meantime--heres the image with Ha added. I re[processed it from scratch. Not totally satisfied with the Ha leakage around the nebulas. I'll have to work on that. Not sure how.
  13. M33

    I had a rare week of exemplary weather. M33 was high in sky. For once my broadband data looked decent. EXCAPT FOR THAT BLUE SUB V. Still don't know what would be in sub but not in flat--moisture maybe? Seems an odd shape for frost or dew. Rodd
  14. M33

    So--upon further inspection--The V that will not calibrate out is only on the Blue subs. But it does not appear on Blue flats taken the same night. There bare 2 issues--1 is the V shaped blotch on blue subs that does not appear on any other filter or in any other flats. The other issue is the V shaped blotch that appears on all subs and on all flats IS removed on all filters except for the blue subs where it is not wholly removed. Here is an uncalibrated blue sub, and the same blue sub calibrated. Note that all smudges are gone (except the mysterious V shape)--but in the calibrated sub you can see the V shape that is on the flat--almost like the flat did the opposite of what it was supposed to do--but only for this area--the smudge at top IS gone). The whitish v shape next to the dark V shape in the calibrated sub is the V shape that was on the flat magnified somehow. Rodd Uncalibrated blue sub Calibrated blue sub
  15. M33

    Thanks Wim. See my discussion below regarding "strange" things in this image I am glad you asked!! Attached is blue sub and a lum sub. Both the blue and lum subs all have this V shaped patch. Also attached is a master blue flat that shoes a similar V shaped blotch--but the V shaped blotch on the subs and the flat does not line up. And they are of different dimensions. The V shape blotch on the flat actually removes a similar blotch on the subs--just like it removed the blotch at the top. But the V shaped blotch on the subs is oinly really visible on Lum subs (and blue after meridian flip). Also attached is a blue sub after Meridian flip that has the same V shaped blotch as is on the flats. Any Idea what is going on? 1) The V shaped patch does not rotate with the camera 2) V shape visible on subs does not appear on flats 3) V shape visible on flats removes a much fainter V shape from the subs (not very visible on subs--but after meridian flip it can be seen faintly) master Blue Flat Lum sub: v shaped blotch seems to be same as in flat Blue sub--V shape definitely not the same as on flat--flat does not correct Blue sub after Meridian flip showing same patch as on flat Please Help!!!