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.
Hi Mabula,
I had a couple hundred frames of M1 taken with a very small FoV (F/10 SCT). Â
Most frames passed Registration with stars found = 504.
About 10 frames failed with stars found = 498, 496, etc.  Numbers just under the 500 minimum.
Is there a reason we couldn't have a lower number of stars found still be a "passing grade" for registration?
Thanks!
Rowland
Dear Rowland @rowland-f-archer-jr,
I am about to release APP 1.072 😉 it has a further improvement in star analysis and it could be the solution to why some frames failed in your case.
The actual number detected, being a bit above 500 or below should not make a difference. Some images only contain very little stars and APP will register those, if the star analysis works correctly.
Some users experienced difficulties because hot pixels were mistaken for stars and then registration on those frames will fail. I think the new release will solve this and I would think this is the issue that you face as well.
You can check yourself if star analysis is working correctly on those frames, by setting the image viewer to the starmap mode. Please check if APP finds stars were there are actually hotpixels 😉
I will try to release APP 1.072 within the next 24 hours !
Mabula
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Hi Mabula -Â
OK, I will try 1.072 🙂
I asked because it seemed like only the images with stars just under 500 were marked as "Failed." I loaded the images and they looked OK. APP is busy now calibrating frames from last night so I can't easily re-run to see if hot pixels were selected as stars. Â
Cheers,
Rowland
It must be an M1 thing as the other day all my M1 images failed, again with an SCT.
Must be a star poor area.
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I ran the images again yesterday and all but 2 passed using per session setting.
Hi @rowland-f-archer-jr and @steveibbotson,
Please let me know how APP 1.072 performs, in star analysis, an extra algortihm is added to better discriminate between hot pixels and small stars. In data with a little amount of stars, APP was detecting some hot pixels as stars and that could have been the reason for registration failures.
Some other users shared their data on which APP 1.070 and 1.071 had problems due to a small star count and detection of hot pixels as stars..., and those datasets do work properly now. If it still fails, please share the data so we can further improve this 😉
Kind regards,
Mabula
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I will run the subs through again.
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I have collected a bit more data since my last stack.
It could be that with using the SCT my stars are also a bit "blobby"
I restacked last night using 1.o73 and at first it analysed and reject a few subs which I agreed with.
Ran the registration with default settings and it rejected them all.
I changed to triangles and then upped the scale stop to 8 (I think) and then manually selected a referance frame.
And with a bit of fiddling in PS.......
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