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 am new to AP & APP. Please forgive me for not being very technical with the software and not knowing the exact cause of my problem. I took 180sx20 subs of M97 WITH a oplolong l-enhance filter. After completing the intergrate process (1-6), my image ends up very "red" & I can not calibrate stars in tools (no stars detected). I get "critical warning: flat-field" but if I add bais frames my image is worse. (Note: I have processed an image with out the filter and was able to get a workable image with the "critical warning". Still don't understand). Any advise welcome.
Thanks, David
WO73, asi533mcpro, AIRPRO for darks, flats & images, Optolong l-enchance filter, Bortle 8 + smog.
@davidk6dlb Hi David and welcome to the forum. The critical warning probably comes from APP not being able to properly calibrate the flats due to the absence of either Dark Flats (darks with the same exposure time, gain and offset as the flats) or Bias frames. Regarding the red color, if adding bias makes the problem worse then my first suspicion is the darks. What happens if you integrate the lights without any calibration frames at all? Do you get correct colors then? Thanks, Wouter
Hi! Thanks for your response. If I only stack the lights I can get a decent image. A little green in the stars but at least I can do some stretching in photoshop (i'm new to PS also). I took my darks (lens cap on), @ 180s same as lights. The flats are with a t-shirt using Airpro on auto. (I did process a galaxy with good results with no filter). "Dark Flats" I have none. The image I posted is light, dark & flat only.
Forgive me not being very articulate ... I don't really know the proper questions to ask.
@davidk6dlb No problem, I will simply continue asking questions 🙂 What application do you use to take your images and did you use the same software to take the darks and bias?
Awesome! I used the zwo asi airpro.
@davidk6dlb If you use the reply button (it looks like a link) then my forum name gets added to the start of your reply and I receive and email indicating that you replied. That way I can respond quicker 🙂
Perhaps you can upload a few lights, a few darks, a few bias and a few flats so I can have a look at your data. Please use upload4 as both username and password for
https://upload.astropixelprocessor.com/
and create a new folder called davidk6dlb_red and put the files there. Let me know when the upload is done and I'll download the data to have a look.
@wvreeven I am trying to log in to upload my files but can't seem to do so.... I used my user name and password and cannot log into the file upload? (Did I reply properly?)
@davidk6dlb You did reply correctly, thanks!
And I wrote
use upload4 as both username and password
so use upload4 for both username and password 🙂
@wvreeven I am so excited for your help I did not read your reply properly. Sorry.
I have uploaded my files.
@davidk6dlb Thanks a lot. I have had a look and the darks are not truly dark. It looks like some light got in so you will have to do those again in a dark environment. Also, the camera temperature is important. Try to wait until the camera temperature is at 10º as well. Finally, the exposure time of the flats is too short and they are over-exposed. The exposure time is too short since it is shorter than 1 sec. Modern CMOS cameras have a rolling shutter and having a short exposure time will introduce an uneven illumination of the sensor. You can dim the light by using a white t-shirt. Search for it online to see how it's done. But the flats are clipped at the right end of the histogram in the green channel so you need to balance that better. Good luck!
@wvreeven Looks like I need to start over and redo them. I have lots of questions about APP. Hopefully I can ask you a few here in the future?
Thanks, David
@davidk6dlb Sure, feel free to ask away. Please do open separate topics for those though.
