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.
After running the Light Pollution Correction tool on my LHaRGB image of M101 there are a series of concentric rings around the object. See attached screen shot. For this image I set the stretch to maximum for easy visibility, but they are visible at 10% stretch.
I turned off OpenGL and they are still visible.
I also saved out tiff copies in 16 and 32 bit and opened the files in Affinity Photo and Preview. Rings visible.
It occurred to me that I started my pattern of boxes in the tool as a rough arc
around the galaxy, but not at this frequency. They were large boxes.
I will run this again tonight using a more staggered pattern to see if it repeats.
Update - I used a different box pattern, moving from top left corner and expanding across the image left to right. Same pattern.
I also opened up 1.083 and used the Light Pollution Correction tool. Same pattern.
This suggests it originates in a previous step. Combine RGB or in the Integration(s) themselves.
When you overstretch a sub, do you see any evidence of these as well?
@vincent-mod I decided to come at this problem with fresh eyes this morning. Procedure:
1) Launch 2.0 Beta
2) Using the LPC TOOL, examine individual integrations (L, Ha, R, B, G) at 15% stretch and 30% stretch. Stretch values chosen for testing convenience.
3) Examine files saved immediately after RGB Combine at 15% and 30%.
4) Examine files saved immediately after LPC at 15% and 30%.
Along the way I was perplexed that the individual integrations did not display in the LPC tool - then I switched from CPU to OpenGL4 and they displayed fine.
Results:
1) No concentric banding noticed in individual integrations.
2) No concentric banding noticed in my older files saved immediately after RGB Combine.
3) No concentric banding noticed in my older files saved immediately after processing in LPC Tool.
4) My most recent RGB combine shows no banding immediately after being saved from RGB Combine.
5) My most recent RGB combine shows banding after being processed in LPC Tool.
As a cross-check, I opened both of the recent files (post-RGB Combine and Post-LPC) in the HSL Tool. Same results. Post RGB fine, Post LPC banded.
It appears my problem is limited to that one file. Earlier files were processed successfully in the LPC Tool.
It occurred to me this effect is similar to trying to photograph a sunset - too much dynamic range for the sensor. So I loaded both files as lights - and the problem file shows 8 bit color space! I hate to say it, but this could have been a very silly user error - some where along the way - LPC tool or HSL Tool - I meant to save it as 32 bit and rushing through selected 8 bit instead.
Later today I will reprocess the RGB file through the LPC tool and see what happens.
