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15th Feb 2024: Astro Pixel Processor 2.0.0-beta29 released - macOS native File Chooser, macOS CMD-Q fixed, read-only Fits on network fixed and other bug fixes

7th December 2023:  added payment option Alipay to purchase Astro Pixel Processor from China, Hong Kong, Macau, Taiwan, Korea, Japan and other countries where Alipay is used.

 

Have to click on overy frame

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(@hubert-hautecler)
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I have 71 frames of comet C_19 L3. When I do the comet registration I have to click on every frame to click on the nucleus.  Is this normal?


   
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(@hubert-hautecler)
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Sometimes it skips 1 frame and then I have to click again. Is this because it's a faint comet? 


   
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(@vincent-mod)
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No, it does that when it can't really detect the nucleus properly. Is it very faint or amongst a lot of stars? Are you using the latest APP version?

If so, we'd love to have the dataset, just so we can test better algorithms for your data as well.


   
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(@hubert-hautecler)
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Hi Vincent, it's near a star, so maybe that's the problem and yes it's faint. I have to confirm almost every frame.  See my pasted image. I will load up the dataset but how do I have to do this?

 

image

   
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(@vincent-mod)
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(@hubert-hautecler)
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I'm still processing them and will load them up when I'm finished. 


   
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(@hubert-hautecler)
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There are uploaded.


   
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(@vincent-mod)
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Excellent, thanks Hubert! We will work with your and other data which proves more difficult.


   
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(@hubert-hautecler)
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Vincent, this is the final registration. It worked fine. Can you tell me from this streched image of this is due vignetting or light pollution? I use flatframes.

image

   
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(@vincent-mod)
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Kind of looks like vignetting, are you sure the flat frames are correct and applied as well? I'll have a look at the data as well, so can probably tell. Light pollution is also possible, but you'd have a lot then indeed. The LP tool should work pretty well on it.


   
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(@hubert-hautecler)
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@vincent-mod 👍 


   
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(@vincent-mod)
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Loading in the lights I noticed in the FITS header that the mosaic type could be different to what is reported. Which is kind of odd to me. I changed it manually to RGGB and that looks better, otherwise the blue channel was more pronounced which didn't make much sense to me.


   
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(@vincent-mod)
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Applying the masterflat, it does work but seems to over-correct a bit, I think the flats could be better in that case.


   
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(@vincent-mod)
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It indeed does involve a few manual actions, but it also processes quite a few automatically. I think the data is somewhat on the borderline of what the algorithm can nicely detect. Nonetheless, always perfect for trying to optimize it.


   
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(@vincent-mod)
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So yes, the flats do have an issue. Not all dust spots are removed and it's over-correcting. This usually is the case with either a bias or dark not being correct or an issue in the flats.


   
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(@hubert-hautecler)
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Posted by: @vincent-mod

Loading in the lights I noticed in the FITS header that the mosaic type could be different to what is reported. Which is kind of odd to me. I changed it manually to RGGB and that looks better, otherwise the blue channel was more pronounced which didn't make much sense to me.

I use Sharpcap Pro and in Sharpcap I can click on Inverted. Sharpcap suggest that this is for APP. Is reverse the bayer. Is that what you are saying?

image

   
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(@hubert-hautecler)
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What do you suggest I do to get correct flats? Bias and darks are from last month.


   
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(@vincent-mod)
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Posted by: @hubert-hautecler
Posted by: @vincent-mod

Loading in the lights I noticed in the FITS header that the mosaic type could be different to what is reported. Which is kind of odd to me. I changed it manually to RGGB and that looks better, otherwise the blue channel was more pronounced which didn't make much sense to me.

I use Sharpcap Pro and in Sharpcap I can click on Inverted. Sharpcap suggest that this is for APP. Is reverse the bayer. Is that what you are saying?

image

Ah how interesting, never seen that before. When I loaded in your data, the standard pattern as reported in the fits header is used and that was showing GBRG. Which I overruled manually to RGGB in tab 0. I guess the setting in Sharpcap will do that then.

 


   
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(@vincent-mod)
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Posted by: @hubert-hautecler

What do you suggest I do to get correct flats? Bias and darks are from last month.

That depends on how exactly you're taking them. What procedure do you follow exactly and what program do you use to capture it. How are you taking proper bias and darks..

 


   
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(@hubert-hautecler)
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Posted by: @vincent-mod
Posted by: @hubert-hautecler
Posted by: @vincent-mod

Loading in the lights I noticed in the FITS header that the mosaic type could be different to what is reported. Which is kind of odd to me. I changed it manually to RGGB and that looks better, otherwise the blue channel was more pronounced which didn't make much sense to me.

I use Sharpcap Pro and in Sharpcap I can click on Inverted. Sharpcap suggest that this is for APP. Is reverse the bayer. Is that what you are saying?

image

Ah how interesting, never seen that before. When I loaded in your data, the standard pattern as reported in the fits header is used and that was showing GBRG. Which I overruled manually to RGGB in tab 0. I guess the setting in Sharpcap will do that then.

 

I will set the values back to normal. 


   
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(@hubert-hautecler)
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Posted by: @vincent-mod
Posted by: @hubert-hautecler

What do you suggest I do to get correct flats? Bias and darks are from last month.

That depends on how exactly you're taking them. What procedure do you follow exactly and what program do you use to capture it. How are you taking proper bias and darks..

 

I use Sharpcap for all my calibration files. I use for the flats a selfmade flatpanel with white chalkpaper. I take 30 flats of 2.5 seconds, my histogram is about in the half. Darks are taken at the same temperature as the lights (- 5°C) with a silicone cap (from Altair) on the camera. No light leaks. Bias the same way but I use the shortest integration time possible.


   
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(@vincent-mod)
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Mmm, never seen such a flat panel. The most important thing there is that it creates a full-spectrum, flat field. Are you sure the panel delivers that? Besides that, some sensors have an issue producing a proper bias signal at the shortest amount of exposure time. I'd suggest a flatdark instead, where you do the same as for a bias, but expose for the time of your flat.


   
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(@hubert-hautecler)
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My flatpanel is like the one with the white T-shirts, only I don't use a T-shirt but white paper. 😊 

Next time I will take a shorter time for my flats so that the histogram is more to the left at 2/3 of the histogtam. Maybe my exposure was to high although it was just in the middle, somewhat to the right side. 

And take flat frames instead of bias.


   
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(@vincent-mod)
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I think your time is fine, it's usually even better to expose for longer, just making sure not to clip on the right-hand side. Reason for this is that you use the full dynamic range of the sensor which can actually help in cases of quite big vignetting.

 


   
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(@vincent-mod)
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ps. I tried to make an artificial flat as well, but I keep having an uneven pattern in the end result. This signals to something creating something that's not a regular gradient. This could be light pollution or a light "shining" into the optics, could this be the case?


   
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(@hubert-hautecler)
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Posted by: @vincent-mod

ps. I tried to make an artificial flat as well, but I keep having an uneven pattern in the end result. This signals to something creating something that's not a regular gradient. This could be light pollution or a light "shining" into the optics, could this be the case?

Maybe light pollution because the nearly full moon was up. A light shining in the optics seems not possible because my setup is shielded by gardenpanels. 


   
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