Hi,
Attached is another example of artifacts present in a single, non reduced (no bias, dark, flat), debayered exposure as rendered by StarTools version 1.3.5.289.
Previous experience (http://forum.startools.org/viewtopic.php?f=4&t=961)] revealed an error in the image capture tool (TheSkyX) when such artifacts were present.
Is this another case of a problem with an image capture tool (Nebulosity4)?
Thanks in advance for your feedback.
--jim
Possible Artifacts in Image Capture?
Possible Artifacts in Image Capture?
- Attachments
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- single exposure from Starlight Xpress SXVR-M25c (OSC) debayered in PixInsight using GRGB Bayer pattern
- GRGB_AutoDev.jpg (472.15 KiB) Viewed 7678 times
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Re: Possible Artifacts in Image Capture?
Hi,
Which artefacts are you referring to in particular? The mottling perhaps? Flats may fix that...
Which artefacts are you referring to in particular? The mottling perhaps? Flats may fix that...
Ivo Jager
StarTools creator and astronomy enthusiast
StarTools creator and astronomy enthusiast
Re: Possible Artifacts in Image Capture?
Sorry for the lack of clarity in the original post. I am referring to the vertical bands - two of which are enclosed in rectangles in the attached, annotated version of the original, screen capture.admin wrote: Which artefacts are you referring to in particular? The mottling perhaps?
I do not understand how flats could fix vertical bands spanning the entire width and height of the image.admin wrote: Flats may fix that...
Re: Possible Artifacts in Image Capture?
Sorry for the wasted bandwidth. I see the image attachment was not included in my previous post do to a 512kb size restriction. So, I have attached it to this posting.
- Attachments
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- screen capture showing vertical banding
- GRGB_AutoDev.jpg (432.97 KiB) Viewed 7658 times
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Re: Possible Artifacts in Image Capture?
Hmmm... not sure I can spot it very well, but if we're talking about vertical or horizontal lines, these would be the hallmarks of "banding". Applying bias frames should help with this. Dithering could also help. Sometimes, saturated wells (as caused by very bright stars) can cause blooming (vertical stripes that may be brighter or darker). The latter is much harder to fix, but if absoluteley necessary, acquiring half your frames rotated by 90 degrees can help overcome the problem.
Ivo Jager
StarTools creator and astronomy enthusiast
StarTools creator and astronomy enthusiast
Re: Possible Artifacts in Image Capture?
Thanks Ivo for your suggestions.admin wrote:Hmmm... not sure I can spot it very well, but if we're talking about vertical or horizontal lines, these would be the hallmarks of "banding". Applying bias frames should help with this. Dithering could also help. Sometimes, saturated wells (as caused by very bright stars) can cause blooming (vertical stripes that may be brighter or darker). The latter is much harder to fix, but if absoluteley necessary, acquiring half your frames rotated by 90 degrees can help overcome the problem.