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.
I use an ASI294MM Pro with ZWO RGB filters and a ASI294MC Pro unfiltered. Every time I process an image with either camera and do a star color calibration the blue stars look like every other image I search for that target but the stars that should look yellow judging by other images always end up red/pinkish. I process the MC unfiltered with default settings, remove light pollution and then a star color calibration. With the MM I process with default settings, remove light pollution from each frame and then normalize. I then combine RGB with RGB-1 algorithm default settings and then remove light pollution from that result and do a star color correction. The results from both cameras have the same colors, but they do not match what I see when looking up the same target taken by other people. What am I doing wrong?
Could you post a few examples of the effect you're seeing? Also, are you combining the RGB with the MM data or really just both separate?
@vincent-mod I have not combined any images from the cameras, but will probably try in the future. I have the MC on a 300 focal length and the MM on a 2,074 focal length. I will upload some images when I get home this evening.
After Combine RGB
After star color calibration
I see and how do the star color calibration plots look like? It may be that you have to adjust the correction a little bit. Also, after this the HSL selective color tool can be used to adjust the red a little as well.
Hi,
I do not know what colour balance you were looking for but assuming that you are also shooting LRGB, your results do not look too dissimilar to my outcomes when targeting globular clusters (but that is not to say that my results are actually chromatically correct).
M13
M94
I use Adobe Camera RAW to tweak my APP results as I find this is easier to use than APP HSL.
I have looked at many images of clusters on Astrobin and many show a preponderance of Blue stars but generally these seem to be NB images.Â
Based on this analysis of Hubbe imagery I think LRGB globular cluster images should show star populations tending towards yellow / red (which I think endorses APPs Adaptive Black Body method).
https://www.e-education.psu.edu/astro801/content/l7_p5.html
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Hoping for an interesting discussion.
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Mike
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Always an interesting discussion indeed. 🙂 In the end, it's always up to what someone wants. The APP black body model is a very nice method to get accurate results, mostly when not using filters and definitely being pure broadband data. When using filters, you may have to change the slopes etc to match the star population and tweak it a bit.
I did not post the pics, but I have my scopes side saddled and captured ASI294MC Pro data at the same time on the wide field setup. The OSC unfiltered image resulted in the same exact star colors which were blues and reds. I have since found a few pics on google with red stars in M5, but the majority are blue and yellow. I too use camera raw for color adjustment as I am used to it.
If I adjust the stars to look more like the colors from the majority of internet pics then the slopes are not even touching the stars which just seemed wrong to me. I just want to have stars as close to realistic colors as possible, but even hubble footage can vary greatly in coloring so it is hard to find a good benchmark.
