Mar 28 2026 APP 2.0.0-beta40 will be released in 7 days.
It did take a long time to have the work finished on this and itĀ will have a major performance boost of 30-50% over 2.0.0-beta39 from calibration to integration. We extensively optimized many critical parts of APP. All has been tested to guarantee correct optimizations. Drizzle and image resampling is much faster for instance, those modules have been completely rewritten. Much less memory usage. LNC 2.0 will be released which works much better and faster than LNC in it's current state. And more, all will be added to the release notes in the coming weeks...
Update on the 2.0.0 release & the full manual
We are getting close to the 2.0.0 stable release and the full manual. The manual will soon become available on the website and also in PDF format. Both versions will be identical and once released, will start to follow the APP release cycle and thus will stay up-to-date to the latest APP version.
Once 2.0.0 is released, the price for APP will increase. Owner's license holders will not need to pay an upgrade fee to use 2.0.0, neither do Renter's license holders.
Hello Vincent, Wouter and Mabula. To my question. How does the quality assessment actually work in APP and what are the steps involved? Do you look at the whole picture or just part of it? I ask because I noticed that the star density is not actually comparable with image shifts (unavoidable with dithering). And wouldn't it be better to specify an area after registration in the light frames that overlaps 100% compared to the rest of the lights. Then the images in the stack can be better judged against each other.
With friendly greetings
Doesn't anyone have an opinion on this? 😟Ā
Hi @minusman,
Quality calculations are revised after each step.
So after 3) Analyse stars, only the star count in the whole image and their median shape (size and roundness) determines the quality score since this is the only thing that we know after that step.
After registration, possible image scale differences are taken into account, so if you shot the data with different camera's, telescopes or sensor binning, APP uses the registration parameters to correct the quality scores that we had after step 3. Furthermore, yes, the registration parameters allow us to use the same area/field of view as the reference frame to correct the other frame scores using the same area as the reference frame area.
Finally after normalization, so images registered and corrected for illumination differences, noise values are also added to the final quality score of the frames.
We will publish the exact formula in the manual that is coming...
Mabula
Hi,
Could I ask a follow up question? Ā I understand that the quality scores of the images calculated by 3) Analyse Stars are used to select the best one as the Reference Frame. Ā Does APP use the recalculated quality scores for the frames in 4) Register or 5) Normalize for any purpose?
Thanks, Jeff
Hi Mabula, thanks for the reply. I just do not know yet which reference range is meant.
1. whole reference frame (green area)
2. or only the area where the images overlap (red rectangle)
Option 2 would have the advantage that one can judge the transparency (by clouds, light pollution, etc.) of the individual frames in relation to the reference frame better on the basis of the star number.
The images above serve only as an example.
Or am I wrong?
With kind regards
Ā
