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2026-10-09 APP 2.0.0-beta48 has been released !

This is mainly a bug fix release for the reported bugs in beta47. In addition it has a significant User Interface performance improvement noticable when you need to process 1000s of images in APP.

2026-10-03 APP 2.0.0-beta47 has been released !

This is a very big release... many code optimizations/rewrites, many parts of APP are much faster and more precise, especially star analysis and registration are much faster ! Big mosaics will go much faster 🙂

And we introduce a new preview filter, which includes the new Adaptive Deep Sky Stretch and a General Levels Stretch, this has been long over due. The old preview filter (the panel on the right side to stretch and preview your data) has not been updated for a couple of years and it is a critical part of any APP session.

Adaptive Deep Sky Stretch or ADSS is a much more intuitive stretch algorithm. It is also color preserving (which is a great new addition in itself ! ) which means that the highlights are no longer bleached, color is maintained from the linear data while stretching. You can simply stretch your data using the sky background level and signal width sliders which work much easier and more intuitive. You no longer need to fiddle with the old complicated sliders with zoom buttons. All the zoom buttons for the sliders are made redundant. And you can enter slider values in the slider value fields yourself. I will make a youtube video in the coming days to explain and fully introduce ADSS. Once the video is ready, it will be highlighted on the forum.

RGB Combine upgrade !. The RGB Combine Tool has been rewritten mostly. The tool is faster and easier to use and most importantly, the Luminance slider to inject a luminance channel or channels into the RGB composite is now working correctly. It no longer bleaches the RGB colors. Combined with the new ADSS preview, you will get much better and easier great composites with great color! I will also explain this in a new youtube video.

remove light pollution problem

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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

Beginner's problem.  I use the workflow in Christian Sasse's tutorial. I have successfully produced several really good images so far. I recently imaged M51 (lrgb). All of the blue frames were bad - the rest were quite good.  I went ahead and made a really nice image from the data I had. The next night, I reshot the blue frames with excellent results. I then loaded the good lrg images and the new good b images.  I combined rgb and had a really nice image.  When I started "remove light pollution", the image went completely white.  I have read about others having this problem. I tried adjusting the b, w, and st sliders. I was able to see my image, but I couldn't get it even close to what it looked like before starting light pollution removal. Any pointers would be greatly appreciated. And thanks to the developers of this software - I'm thrilled that I'm finally producing images after having no success with other programs!



   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Mmm, you calibrated all frames with the correct calibration files? It might be that dark or bias calibration is the issue in that case. Not sure, for that I would need to check myself with the original raw data and raw calibration files. If you want to upload a set (good versus the white version) I can give you the link.



   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

That would be great if you could take a look.  The only calibration frames I used were 15 darks.



   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Those may have an issue, could you just try without them to see if it happens again?



   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

 

 

I have another problem which is probably related. Took data on M82 last night. The good news is that only 2 out of 160 frames were not registered. However, when I combine LRGB there is a problem.  If I remove the luminance channel, the image is normal. When I add in the luminance channel, it's messed up. I'll attach screens shots of both.

Screen Shot 2021 03 09 at 11.17.38 AM

 

Screen Shot 2021 03 09 at 11.17.58 AM


   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

@vincent-mod I'll try that and let you know what happens.



   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

Indeed that did the trick.  What do you suppose is wrong with the darks?  I took them in between another imaging run and this one, with the same gain and exposure time.



   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Difficult to say, I just notice that when something is up with calibration, it usually are the darks. Could be a number of things, what settings do you use when making the dark and what do you do in APP itself?



   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

@vincent-mod Same settings as the imaging run. I follow Christian Sasse's workflow exactly - load the lignt frames, load the dark frames, then hit calibrate.  Correction - I hit "create masters and assign to lights"


This post was modified 6 years ago by Ed Wallace

   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

Mmmm, maybe they weren't completely dark? Is the offset ok as well on them?



   
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(@edwallace)
Red Giant
Joined: 6 years ago
Posts: 31
Topic starter  

@vincent-mod Lens cap on camera, camera inside thick black glove (outside at night).  I'm ashamed to say I do not know what offset is. I will learn about that tonight. Now I have to go to work. Thank you for taking the time to help.



   
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(@Anonymous 174)
Joined: 9 years ago
Posts: 5702
 

An offsets is a noise floor basically for the sensor (if I'm not saying this incorrectly 🙂 ). But those are for astro-camera's.

In your case, I probably would need to look at the dark itself. Light can still create an issue, might also come from within the camera even. No idea if that's the case for you of course. No light in the garden at night from neighbours?



   
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