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,
I often did not use flats in the past because I had no problems with dust and the very weak vingnetting in my system could easily be removed with the great light pollution remove tool in tab #9.
Actually I am taking part in a coordinated project and need to share old data as calibrated data to the other partners who use a different software. So I tried making artificial flats with the "correct vignetting" tool which delivers nice flats as it seems. As it is important to share the best quality possible I would be glad if someone would check wether or not the following workflow is correct:
01 load the uncalibrated lights
02 load masterdark (MD)
03 load masterbias (MB)
04 load bad pixel map (BPM)
05 calibrate lights with masterdark and masterbias in tab #2
06 save dark-calibrated files in tab #2
07 remove light frames from list
08 load dark-calibrated files
09 choose one representative sub
10 apply the "correct vignetting" tool in tab #9
11 save with option"save artificial flat" checked
12 remove the lights from the file list
13 load the uncalibrated lights
14 calibrate the lights in tab #2 with MF(art.), MD, MB, BPM in place
15 save calibrated files in tab #2
16 share calibrated light only, no need to share the calibration files
Many thanks in advance 🙂
CS Pete
So Mabula once shared the following advice regarding the creation of an artificial flat:
On all lights if you make an artificial master flat, select "create artificial flat". This will save the correction model as an artificial Master Flat. You can then use this Master Flat, just like an original master flat to correct the vignetting.
To get the most accurate result, first calibrate the lights with a master dark or master bias (create masters & assign to lights button, tab 2). Save these calibrated files (tab 2 all the way down). Then clear APP or reload APP and make the artificial flat using one of the calibrated frames (load in 1 of the calibrated lights). Then load in all the calibrated lights and add the artificial flat, calibrate again and see if that works.
Thing is though, if you don't need flats and it looks fine already, I'd say that is better than adding an artificial flat maybe.
Thank you very much for the fast response, Vicent!
So your advice is to calibrate the already (pre-)calibrated subs using only the artificial flat (using no master dark and master bias). That makes much sense if the flat does not contain any readnoise by its nature. In that case the calibration warning that APP generates does not apply and can be ignored?
You wonder why I try to make artificial flats while my images look fine without flats. For me the processing was fine without flats because I could use the gradient removal tool on the integrations of only my own data. The plan here is to stack and combine different sets of data from different imagers. Some will work in APP, otzers in PI. So I worry that my data that are shot without flats would inject gradients and/or make problems for the others. That is why I'd like to share calibrated data - ready to use so to say.
Thanks again!
Pete
T
Yes, it should work like that indeed. Do have to say I never use an artificial flat, so if anything doesn't work out, let me know. 🙂
Yes, when sharing data it's nice to have the best data you can get indeed. Point taken.
