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.
Hello,
I'have an integration of 60 lights of 30s of California Nebula.
TS 102 reducted and flattened, L Enhence filter, no guiding.
I join the JPEG of the result of integration with the default parameters.
Why do I have this strange pattern all over the picture ?
Thank you for your help.
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This is called "walking noise" as far as i am aware. The solution to this is dithering but this depends on your setup and if it is able to do it automatically. It can also be done manually but that would require you to stay with your setup all the time. At least you know the name now 🙂 I do not tihnk this is easy to remove with software in post processing.
Aha!
So that's Walking Noise? Helpful to me as well, since I got the same pattern in a stack of Markarian's Chain I took a few nights ago (52 x 4 minute exposures). I thought it was my camera sensor (DSLR) getting to hot and not taking enough dark frames to subtract.
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Need to look into dithering myself apparently. Thank you.
Yes, that's a classic example of walking noise. Dithering is the best solution for that, I tend to do pretty big dithering steps like 5-10 pixels. If I have a lot of subs I dither every 3 frames, otherwise every frame (which might be a bit over the top, depends on the result).
@vincent-mod @wheeljack And if you increase the dithering step to 20 pixels for example, the noise level really goes down to the point where dark frames are useful for amp glow and the bad pixel map. Dithering, once you add it to your guiding routine, really does help and I think you will be surprised how good your images are underneath all that walking noise once you take new subs.Â
Perfect. Thank you so much for your replies.
Yes, if you have bigger artefacts, bigger dithering steps will help. It's an old saying.. dither or die (I would rephrase that to something more gentle, but I didn't invent it). 😉
