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Hello,

I took a shot of M13 as a first test of my new orion 8 f/3.9. I have a couple of questions about the final result.

Equipment list:

  • orion 8 f/3.9
  • mount skywatcher eq6r-pro
  • canon 500d - astro-modded by me
  • 40 exposures of 90 seconds and 40 darks
  • 200 bias
  • 200 flats
  • capture software: nebulosity4
  • guide camera: zwo asi120mm
  • guide scope: svbony 20 (80mm - 400mm)
  • guide software: phd2

Processing:

  • siril preprocessing: align/callibrate/stack)
  • siril post-processing: green nois reduction/ photometric noise reduction (very cool!)/deconvolution

Result:

I attached a screenshot of siril (as the tif or jpg export did not show these "problems")

My questions:

  • after preprocessing, I still have 2 problems (see the marked areas); what can be the cause of that? Are my flats not "correct"? The big mark, is a spot on the sensor, that is the "collateral damage" of me removing the Ir-cut filter. The other mark must be an other issue, I don't know so far
  • the right part of the picture, shows some sort of glow; there was no moon during capturing; I live in a bortle class 5 area, but street lights are dimmed after midnight, till 05:00am and shots were taken around 01:00am. what can cause this glow

Other remarks are very welcome - I hope to learn from it.

Thanks in advance,

AstroRookie

Screenshot 2020-09-19 at 16.09.17.jpg

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The glow could still be some sort of LP or just a sky gradient, should not be a problem as such.

The marks, are they just dirt or physical damage?

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4 hours ago, wxsatuser said:

The glow could still be some sort of LP or just a sky gradient, should not be a problem as such.

The marks, are they just dirt or physical damage?

Hello Mike,

the big one on the right below, is dirt I guess and hope; it appeared after I modded the camera. When I used the built in sensor cleaning feature, it's shape changed, so that makes me think it's dirt (I will have it checked and hopefully cleaned by a profession photographer). The other one, I don't know where that comes from, to be investigated. Thanks for your input!

AstroRookie

PS: Nice pictures on your wordpress space

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