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 am very happy with the new Multi-NB extraction method, it saves me a lot of time. Question I have is how should I approach drizzling of the Ha data. Should I still stick to Bayer drizzle, or is it different because this is greyscale data? And what about the droplet size in this specific case? Any advice or guidance is appreciated.
Hi Tom @tvanpeer,
Thank you very much for your message. Great to hear that the new Multi-NB method is working nicely for you 🙂 !
Question I have is how should I approach drizzling of the Ha data. Should I still stick to Bayer drizzle, or is it different because this is greyscale data? And what about the droplet size in this specific case? Any advice or guidance is appreciated.
The data, allthough grey is still Color Filter Array = CFA data that needs to be demosaiced/debayerd, so yes, use Bayer Drizzle. Bayer Drizzle settings I recommend are :
- scale 1.0
- droplet 2.0
- drizzle kernel Gauss
If the result looks good, but you want to see if you can get it sharper, try lowering the droplet size to 1.5 for instance. By lowering the droplet size, you might increase sharpness in the result, but it can also become more noisy so you will need to find a balance that suits you most 😉
Let me know if this helps.
Mabula
Thanks Mabula, that is certainly the starting point I was looking for. In my RGB set for the same target I could scale up to 2 with droplet size 1.5. I assume that if droplet size 2.0 works for Ha, I still need to go to scale 2 to get to the same resolution as my RGB set?
Hi Tom @tvanpeer,
yes it would 😉 Since it is Bayer Drizzle and you only work with the CFA pixels, to make your integration, you will need plenty of images though if you increase the scale. I would suggest to set the scale to 2, the same as your RGB and then vary the droplet size so you get the most preferred balance between noise and sharpness in your Ha data.
Mabula
I hope 12 hours of Ha and 20 hours of RGB will be enough. The drizzled RGB image seems to look pretty good already.
