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,
this might be a silly question, but I'm wondering what the red color on my master flat means.
Is there an error, or is it normal?
Thanks.
And get well soon, Mabula! 😉
I'm pretty sure when I process data from a colour camera the masters are all listed in grey.
You do know you shouldn't use bias and darkflats in the same integration, right ?
I don't know what would happen if you used both - maybe the masterflat ends up with invalid values. Maybe that's why its shaded red - just a guess.
JC
@connor231 Actually, no, I didn't know (why), and I've been doing it that way for years, lol.
I changed my technique for flats when switching to NINA, no error message for the master file, no error message during integration.
I tried my old masters, no red line.
thanks
The short answer is that bias frames and darkflats are two slightly different techniques for doing the same adjustment. This adjustment shouldn't be done twice.
All digital imaging sensors include a bias signal before the ADC stage. This allows the electronics to more reliably process the signals at low light levels, but it slightly distorts the mathematics when applying masterflat calibration. So it needs to be removed when creating the masterflat.
Bias frames are the traditional tool for calculating this adjustment, but darflats are more reliable with modern sensors.
If the adjustment was applied twice the resulting masterflat would be overcorrected for bias.
I don't know what APP does if both are supplied. The best case is that it may only apply one adjustment - in which case no harm is done, but the unneeded bias frames (or darkflats) are just ignored.
The worst case would be if APP tried to apply both. This would distort the masterflat and might lead to invalid values/data errors.
If the bias frames are working for you, then you could just stop doing the darkflats. On the other hand, if you wanted to future proof your workflow for modern sensors such as the IMX571 then I would recommend ditching the bias frames and using darkflats. However, the exposure time for the flats and darkflats should be increased to about 1-2 seconds for best results.
JC
(And get well soon, Mabula! 😉)
