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'm trying to understand the different registration options better. I didnt see anything in the quick reference manual. I have the NIKKOR Z 14-24mm lens which at 14mm has a FOV of 115 degrees. First question simply is - what's going to work better for this FOV and why - projective or calibrated projective?
When using calibrated projective, what are the tradeoffs between rectilinear, equirectangular and mercator? Is it speed/quality or is it more about how you want your image represented? The tooltip talks a lot about the algorithm approach but not a lot about the outcomes/use cases.
Maybe I should do some reading on the technical differences.
Hi Dane @donkrx,
for that lens I would always use calibrated projective, on a mosaic project it is critical even !
The technical reason is: the normal projection of a normal photography lens (or telescope) is rectilinear. But the rectilinear projection only works okay with Field Of Views smaller than 120 degrees.
If the field of view becomes larger than 120 degrees any image that is rectilinear projected gets distorted big time... it can blow up to infinite dimensions when you have a FOV near 180 degrees.
Calibrated Projective registration model makes APP calculate camera parameters enabling you to use different projections. So in that case, you need to use calibrated projective model and then choose any other projection model than rectilinear. The differences between equirectangular or mercator are well described i think on wikipedia?
Mabula
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Right, well, (using DDC) when I use calibrated projective, the registration RMS is very bad - averaging about 6 over all of my lights with a maximum of 10! Hence this question because it seems to me like you said that this lens might benefit from a different projection model.
I have not tried integrating the equirectangular or mercator projections but the rectilinear was pretty bad with everything out of alignment, even the image center.
When I run with the standard projective option though, the result looks good. Registration RMS ranges from 0.2 to 0.54 and seems to get worse with my later subs so maybe I did a bad job adjusting my camera position (shooting static from tripod).
