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gorann

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About gorann

  • Rank
    Sub Dwarf
  • Birthday 19/05/59

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  • Website URL
    http://www.mn.uio.no/ibv/english/people/aca/gorann/index.html

Profile Information

  • Gender
    Male
  • Interests
    Astrophotography
  • Location
    Värmland, Sweden (59.77 °N)
  1. Taking a break from writing - NGC 7000

    Great! The wall in a way I never seen before. Unreal (in a positive way)
  2. NGC 5128 - Centaurus A in Close-up

    You have done it again Fernando! Keep on spoiling us with great images.
  3. Good prices but to me it sounds like a bad idea to sell your cooled ASI and go for DSLR if you are going to Australia. DSLRs are ok here in Sweden but I tried DSLR astrophoto last time I went to Australia and the heat just made it impossible - much too much noise. You do not only need chilled beers but also a chilled chip down there!
  4. Some of you may have seen my post yesterday of this object in wide field taken with the 135mm Samyang (@ f/2) and a Canon 70D (unmodded). That same night I run the camera both before and after the meridian flip but the framing then became quite different (I focused on maintaining the framing of the 5" refractor sitting side by side and had no separate control of the Samyang). So, I decided to process the data from after the flip separately as I had quite a large number of exposures to keep the S/N ratio high and did not want to do a major crop. When I now processed the data I collected after the flip (81 x 1 min at ISO1600), I more or less consciously put more emphasis on bringing out any surrounding nebulosity and not suppressing the star filed, and the result is remarkably different. I post the image from after the flip (top) and before the flip (bottom = same as I posted recently). Maybe it shows that I am not very consistent in my processing and run more on inspiration than a consistent workflow. Maybe I should be worried about this? Stacking in Nebulosity 4 and processing in PS CS5. Do you guys also like the top image better? I think I do - at least right now.
  5. Tack Martin! yes, those Samyangs 135 are possibly the best. Somehow they have managed to get rid of almost all coma even at full opening (pixel peepers will see a tiny bit in the corners), and for a very reasonable price. Also, with an APS-C there is not much vignetting (some is there but in this case I did not see the need for the flats I took - a run of Gradient Exterminator was enough).
  6. NGC4038 - The Antennae, Arp244

    PS. If you use the "equalize" function in PS, which is doing some kind of extreme stretch, you get a really ugly image but it is very informative since it reveals if there is any signal to bring out, and in your case there is a lot of signal from the antennae, and probably also a gradient but it is apparently minor since it is not apparent in your image.
  7. NGC4038 - The Antennae, Arp244

    Using curves and layers in PS as Olly suggested, this is as far as I could go with your image. There are definitively antennae there and a bit more dust to be found around the galaxies. With the original 16 bit image you could probably do better. I also think your image would be improved by shrinking the stars so that more emphasis is put on the galaxies (In the second image I used the RC Astro star shrink filter for PS).
  8. Here is the wide field taken with the 135mm Samyang (@ f/2) sitting side by side with the 5" reflector (which simultaneously took the close up of NGC7822 that I previously posted). Not sure if this was the best object for a wide field since and it was a bit odd to process such an undersampled image (6.6 "/pixel) with so many stars. Still, I got it for "free" while I took the close up with the 5" apo. I post also the close up for comparison. Equipment: Samyang 135 f/2 with a Canon 70D (ISO 1600) side by side with a ES 127ED apo and a Canon 60Da. All on an EQ8 on a pier in the obsy. Guided with PHD2 and a SW80 with a QHY 5LIIM. Exposures: Samyang 100 x 1 min. ES127 31 x 8 min (both at ISO1600) Comments most welcome! Cheers
  9. Cygnus Wall - final (for now)

    Yes, enough clouds around. There is a theoretical possibility for me on Monday night here, but otherwise the forecast for this corner of the world is only good for processing
  10. Cygnus Wall - final (for now)

    Wim, So you are retiring your DSLR. I just bought another one, a Canon 60D (ca 300 Euro used on ebay in great condition) for my Samyang 135 to sit side by side with the 60Da on one of the scopes. Seems impossible to get hold of a used 60Da so at least with a 60D I will not be confused fiddling with the settings. Yes, I know, and the plan is also to start using my ATIK more. In any case, I had a go at your image to see what the standard PS tricks could do. So, some High Pass filtering, a bit of local contrast enhancement, selective star shrink and a tweak of the curves and red tone. Finally some NR and gaussian blur to fight the red-green noise. I hope you do not mind and I am not sure it is better, but it is different. Cheers
  11. DIY Rain Alarm

    And, yes, the water makes a connection between the two leads. Putting a wet finger between them sets off the alarm. Thinking about it, pure rain water may not have enough ions to allow conductance between the two leads, so it may be a good idea to put a few grains of table salt into the funnel.
  12. M27 with Marcel Vonk.

    Fosters? Is that "beer" served in France? In Australia I hear that Aussis do not drink it , they only export it...
  13. M27 with Marcel Vonk.

    Got it Olly
  14. DIY Rain Alarm

    Thanks! We live on the country side so my closest neighbor, Maria, lives 100 yards away. And the siren is indoors and only 85 dB (I stayed clear of those with a 110 dB siren - that could have stopped my heart). In any case. Maria is very understanding and when there is a clear night and she sees that I have slid off the roof of the obsy, she turns of her outdoor lights.
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