Strange artifact on...
 
Share:
Notifications
Clear all

9 July 2020 - APP 1.082 has been released which contains one important bug fix. 1.082 has full Fujifilm RAF support, so that includes SuperCCD & X-Trans camera's 🙂 !

9 July 2020 - New and updated video tutorial using APP 1.081: Complete LRGB Tutorial of NGC292, The Small Magellanic Cloud by Christian Sasse (iTelescope.net) and Mabula Haverkamp

2019 September: Astro Pixel Processor and iTelescope.net celebrate a new Partnership!

Strange artifact on mosaic  

  RSS

(@thedwo)
White Dwarf Customer
Joined: 12 months ago
Posts: 13
June 2, 2020 00:12  

Hi

I have three sets of data taken on successive nights. the first two nights they are pretty much in the same location the third being a little to one side but with more than 50% overlap.

I tried to process all in one and resulted in the attached image. You will see a striped pattern on the right hand side.

I then processed nights 1 and 2 together and the image was OK. I then processed night 3 data, which again gave a good image.

Assuming that there might have been a glitch the first time I tried the mosaic of the 3 nights, I repeated the exercise. But the image again had the stripes.

All the above processing was done on APP default settings.

Can you guide me as to what settings I perhaps should use?

Frank

GamCyg mosaic

 


ReplyQuote
Topic Tags
(@minusman)
Neutron Star Customer
Joined: 3 years ago
Posts: 173
June 2, 2020 09:20  

The stripes look like Walking Pattern Noise. Can be removed with dithering and outlier rejection.
With kind regards


ReplyQuote
(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 2, 2020 11:24  

You did use mosaic settings or just regular integration? I'm seeing some variations and not a great blending together of the panels. Did you use MBB and LNC?


ReplyQuote
(@thedwo)
White Dwarf Customer
Joined: 12 months ago
Posts: 13
June 2, 2020 17:25  

Hi 

I've just repeated the processing and used dither, LNC and MMB - although I have to admit I an uncertain of the tecnicalities of these settings. The new image is virtually identical to the one I attached when opening this thread.

Rather than send the image, I think the title of the saved image may help you in seeing what actions were performed.

St-avg-8760.0s-AR_LN_6.0_3.0_none-x_1.0_LZ3-NS-full-qua-mult-sc_BWMV_nor-AAD-RE-MBB5_1stLNC_it2

I hope this is helpful

Thanks

Frank


ReplyQuote
(@minusman)
Neutron Star Customer
Joined: 3 years ago
Posts: 173
June 2, 2020 18:44  

It might be better if you can upload some raw images. From each panel 2-3 lights, and possibly Master Dark, Master Flat.
Then you can better judge what is going on with the picture.


ReplyQuote
(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 2, 2020 18:48  

Yes that would be nice. @thedwo could you upload some raw lights (like 10 for each panel), your master bias, master dark and master flat (if you have those) to our server? Login/password is: appuser

Please create a directory with "thedwo-integrationArtefact" and upload in there. I will have a closer look then, thank you!


ReplyQuote
(@thedwo)
White Dwarf Customer
Joined: 12 months ago
Posts: 13
June 2, 2020 19:23  

Hi Vincent

OK but please advise how I access your server?

Frank


ReplyQuote
(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 2, 2020 19:53  

You can click on the link in my post, the words "to our server". Then the server is loaded and you can enter the username and password.


ReplyQuote
(@thedwo)
White Dwarf Customer
Joined: 12 months ago
Posts: 13
June 2, 2020 20:32  

Hi Vincent

Thanks. All uploaded. 10 of each from 3 sets of lights and a Master dark. There is only a dark as you may recall from a separate thread I had problems with images taken using a different capture software.

 

I hope this enables a solution to this problem

 

Thanks again


(@minusman)
Neutron Star Customer
Joined: 3 years ago
Posts: 173
June 2, 2020 23:42  

Hey, Frank, found the problem. The Bayer CFA Pattern must be changed to GBRG in 0.
The correct RGGB is in the Fits header but apparently your images are mirrored in the Y-axis in the capture software. I came to this through the Masterdark. Because I'm using the same camera and the amp-glow is very pronounced in my upper right corner.

Here is the finished stack.

Mosaik RGB session 1 session 2 session 3 1stLNC it1 St

These black stripes should also disappear through dithering.

Bildschirmfoto von 2020 06 02 23 21 54

Quick Processing 

Mosaik RGB session 1 session 2 session 3 1stLNC it1 lpc cbg csc St

 

 

This post was modified 1 month ago 2 times by minusman

(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 3, 2020 09:27  

Hi @minusman did you do this on the uploaded data? If so, thank you very much. This seems like that removes that pattern as well.


ReplyQuote
(@minusman)
Neutron Star Customer
Joined: 3 years ago
Posts: 173
June 3, 2020 09:44  

Yes, these are the uploaded data, but unfortunately not all lights have the appropriate masterdark and flats.

With kind regards


ReplyQuote
(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 3, 2020 09:58  

Right, well that wasn't the biggest issue anyway it seems, is the mosaic algorithm the only thing you changed for that pattern to go away?


ReplyQuote
(@minusman)
Neutron Star Customer
Joined: 3 years ago
Posts: 173
June 3, 2020 10:50  

Yes changed the Bayer pattern.


ReplyQuote
(@thedwo)
White Dwarf Customer
Joined: 12 months ago
Posts: 13
June 3, 2020 12:31  

Hi Vincent/Minusman

Thanks for that info. One thing though, you say use GBRG in 0. What do you mean by 'in 0'?

I find the whole thing rather weird. Up to several months ago I was using ASICap for capture, creating darks, etc. Then these FITs were processed in APP, with no problem, including mosaics.

Then around April I started using the composite package CCDCiel (a bit like SG Pro & NINA) and that's when I started encountering processing problems, culminating in an earlier post where I found that the darks taken with ASICap and processed with CCDCiel captured lights, in APP gave a weird effect of the amp glow which showed on two places right hand side - upper and lower. This indicated that the Dark had removed the glow from the light in a different place from where is was on the light - one had been inverted. 

Previously amp glow had always been seen on upper right, indicating that when captured in CCDCiel the lights had been inverted.

I would appreciate your conclusions on this as to how I could make the settings in future.

I have to say, I am tempted to revert back to using the ASI native capture software, but CCDCiel has been useful in easily handling plate-solving and auto-focus, in one package.

A fellow astro club member, with identical setup using the ASI294MC-Pro camera, is using NINA with no problems.

Any advice appreciated.

Frank


ReplyQuote
(@vincent-mod)
Quasar Admin
Joined: 3 years ago
Posts: 1913
June 3, 2020 12:54  

The change in software might very well have influenced your data in a sense. What some packages do is not providing more standard fits keywords or simply don't provide any so APP can't know certain things about your camera, sometimes set a flip tag on (which might be the case for you) and sometimes they change the resolution compared to the other package. Therefore it's always best to settle on 1 package to do the capturing and when you switch, making very sure the data is still presented in the same way.

0 btw is tab-0, so on the tabs in APP on the left side, with all the steps to take, 0 is the first one and it has the mosaic algorithm setting in it.


ReplyQuote
Share: