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 have a set 0f 64 subs of M31, but on close examination I see that a number of them have streaked stars. Can I set the outlier parameters so that APP will reject these subs and not integrate them into the stack?
Thanks,
Rudy
Hi Rudy,
There are several ways in which you can handle this.
After registration, you will see information in the FWHM min, max column in the bottom frame list panel. The frames that have elongated stars will have big differences between then minimum and maximum value. Also, the quality score will be much lower than the other frames. Based on that information, you can
- manually deselect these frames (in 1) load you can then remove the deselected frames with the clean button to the right of the load lights button), they won't be included in the integration then
- in 6), use the lights to stack slider , to exclude the frames with the lowest quality scores, these will be the frames with the elongated stars.
- or you can just include them in the integration and try to use star shape weights in 6) integrate. This will have the effect that the frames with the elongated stars will still contribute to lowering the noise in the sky background, while maintaining round stars in the integration. So frames with elongated stars will have a much lower weight than frames with round stars. If you have a couple of frames with elongated stars, then this will work very well 😉 and is preferred over option 1) and 2), because the Signal to Noise Ration with method 3) will be better.
Using outlier rejection can be helpfull to shave off the elongated star shapes as well, but only use it as a last option, because if you set the outlier rejection too strong, the noise in the integration will be higher. Using star shape weights, in most cases, is by far the best option if your stack contains frames with elongated stars 😉
Kind regards,
Mabula
Thanks Mabula,
This looks great, I will give each of these solutions a try.
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Have a great day!
Rudy
