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 all,
This is my second time trialling APP. First time around I didn't know what I was doing, this time a year later I think I'm more clued up - but I'm still not quite getting the results I'd expect when compared to the free Deep Sky Stacker, and I'm wondering whether I'm doing something wrong here.
I've been testing them against each other, trying to process them as closely as possible, and honestly I'm not seeing much of a difference. My hardware is a modded EOS1000D, Sky-Watcher 130PDS on an NEQ6. I'm capturing using APT, then stacking in DSS using the Auto Adaptive mode, and in APP using the recommendations here, then taking the linear output and post-processing in StarTools. I use 25 flats, 25 dark flats and 50 flats each time.
Here are some examples, without any denoise so you can see what's going on.
Now, I'm probably still going to invest in APP because I've just started doing some Ha work and it beats DSS hands-down for that. But, I would kind of like APP to do much better at RGB work than DSS too, especially given the price, and given the amount of time it takes to process.
Is there anything I might be doing that is really badly wrong here, or some button or switch or tick box I should be looking at? Or is this really just a reflection of the limitation of my gear/technique?
Thanks, Brendan
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The difficulty with comparing different packages is that they all have different algorithms. A lot will also depend on how you stretch etc. In this case it might be that your data is already very good, combined with it being not overly complex and then the differences will be in the details/noise etc. It won't always be day and night. However, I do know that APP has very advanced calibration algorithms that are simply better, it allows for much better light pollution correction later on, making seamless mosaics, etc.
Thanks Vincent. I have since done more comparisons and I can see that the stars are tighter with APP than with DSS. Also, it's very much better for Ha data, so I've decided to invest in a year's rental. 🙂
Very much appreciated Brendan! I hope you'll find it works nice for more complex datasets as well. If you have any questions, always happy to help. A new release with quite a few improvements is close as well.
