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rotatux

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About rotatux

  • Rank
    Star Forming

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  • Location
    France
  1. M44 Beehive Cluster

    Nice star colors... just wondering whether there's more depth to it : what exposure (sub length and number, iso, focal and aperture) was that ?
  2. Imaging with the 130pds

    Your colors are lovely, especially the nebula. If I was picky I would say too strongly blue stars and missing gradation in red/orange stars, but the subject is the nebula and it has IMO nice red-orange-grey-blue variations so nothing to complain Wish I had an occasion to get that one but weather decided otherwise and it's now probably off for me til next year.
  3. The Little Dumbell

    I prefer the full-FoV version too, as I like to see objects in context (and still possible to zoom in the full-res image). Nice color and shape details in the nebula.
  4. This shows low or no aberrations => is it the full FoV or cropped ? (I would opt for the latter since that's the FoV I have with a 135 on my MFT sensor...) That 135 looks nice however, which one is it exactly and what aperture ratio did you set for capture ?
  5. m38

    Yes but part of the story: this one only handles monochrome gamma and black/white points of the display. You have to use something that will let you calibrate colors also. Searching "color gamma calibration images" gives things such as http://www.covingtoninnovations.com/DSLR/cal/MonitorCal.gif or http://www.normankoren.com/GammaRGB.jpg or http://www.ballisticpublishing.com/call_for_entries/colour_calibrate_gama2_2.jpg That's typically what I use to grossly calibrate my displays (that is, unless the display is definitely reluctant to displaying correct colors, such as mine at work).
  6. m38

    I can see the presumed blue stars as white... Maybe red pushed a bit too long masks blue ? On my recent 1st try at this target I refrained from saturating colors too much, and I got stars less red and more blue-white (on my own mostly-color-calibrated viewing devices)
  7. The "No EQ" DSO Challenge!

    M38, the Starfish cluster, and its nice little friend NGC1907. Which is the full size for image posted in my gallery here:
  8. Orion and Running Man

    Hello, looks good but sad it's a PNG, far too heavy to view full size here...
  9. Nice colors... highlights interesting features and chemical composition. Brown a bit too high for me, but that's personnal taste. PS: image seems switched L-R with reality if i'm correct
  10. The EQ3 DSO Challenge

    Hi Nigel As you tried 1:1 and 1:2 Ha/O3 ratios and I somewhat liked aspects of both but not fully, I wanted to try 1:1.5 ratio by averaging the first two jpegs in Gimp; Unfortunately they are neither aligned nor same scale. FWIW it would give something like that -- whould be nice too.
  11. Imaging with the 130pds

    I do use darks, which dates back to my old hybrid E-PM1 camera having strong and regular (from shot to shot) thermal noise. YMMV, as the correction brought by darks varies heavily from cam to cam : IIRC most Canon owners here don't do darks. My new E-PL6 has very low thermal and read noise, so I'm in the process of testing the replacement of darks by flats+bias.
  12. Equipment and sites

  13. I didn't check v4 but at least up to v3 it only handles 8-bit images, so that may be a severe limitation for you. OpenCV should be more flexible, it's more oriented to computer vision as name says, but has strong general image processing features, and (the killer feature) manipulates images as NumPy arrays.
  14. 20170923 M45 Pleiades (200om)

    Not a focus problem, it was dead on as far as I can tell. Such saturated / somewhat wrong colors come from applying a star-based B-V color calibration on an image with stars bloated by halos of aberrant colors. Colors and halos are exactly the same without didymium filter, but the filter allows me longer subs without saturating the background. IMO my lens model is of the poorly-coated variant (Oly made another variant of same 200/4 but with MC). Hence CA produces strong halos of different size for blue (bigger) and red (smaller). The end result depends on original star colors, but typically shows outer blue then inner red or purple. I hope to try a technique based on star filters to remove the halos someday...
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