MAY 4 2026: APP 2.0.0-beta44 has been released !
New improved internal memory controls should now work on all computers
May 1 2026: APP 2.0.0-beta43 has been released !
Improved internal memory controls (much more stable and faster on big datasets), fixed CPU image viewer, fixed Narrowband extraction demosaic algortihms.
Apr 29 2026 APP 2.0.0-beta42 has been released !
New improved Normalization engine, Fixed random crashes in integration, fixed RGB Combine & Calibrate Star Colors, fixed Narrowband extraction algorithms, new development platform with performance gains, bug fixes in the tools, etc...
Apr 14 2026: Google Pay, Apple Pay & WeChat Pay added as payment options
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.
One reason to take N frames of a subject, rather than one long exposure is that during stacking it is easier to get rid of anomalous things like airplane trails.
With N frames, simple averaging would drop the intensity of an anomaly by 1/N. That is nice, but outlier detection in the stacking algorithm - like kappa-sigma or others can improve on that.
But it obviously takes some number of frames for this to be effective. In the extreme case of N=2, the outlier detection can't really work very well. Even if it did pick the right frame to throw away, you would be throwing away half of your exposure.
My question is what is the minimum value of N where the stacking N frames with outlier detection in APP do a good job? Â
My guess is that it is on the order of N=10, but I am not sure.
The cost of N becoming large is read noise, but many modern CMOS cameras have very low read noise - so low that sky background dominates it in many cases.  Â
About 25-30 frames, give or take, for the best rejection. Less will still work, more works better, but about that amount is the minimum for an optimal correction.
ok, thanks!
