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.
Hello,
I am trying to improve my calibration scheme, now producing master darks and flats for all gain settings that I've been using so far with my camera (ASI385MC).
When averaging the dark frames, should I use 'no rejection' or can I use e.g. a MAD rejection? I tried both, and I understand that the number of hot pixels and the high-end distribution is different for both cases. But I don't understand why the median value is also different. For example, with gain=150 I get a median value of 4 with rejection, and 6 without rejection. For gain=300, I get again 4 with rejection, but 11 without. Which one is correct, and more importantly, which method should I use to calibrate my flats?
Also, the bad pixel maps look quite different when I run with / without rejection. I have read in another thread that _long_ darks should be used to compute bad pixel maps, which is not my case here since I took the darks with same exposure time as the flats. Does this mean that I can't use these to derive a bad pixel map?
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Cheers,
Fred
First of all, darks with the same exposure time as the flats are more like bias frames with potentially some extra hot pixels. They are good to calibrate the flats with, but not for your regular images. So it's best to use a very long exposure dark for the bad pixel map, but if you don't have that, use the longest you have (which usually is 5-10 min depending on your light frames exposure time) + calibrated flats and bias. You can then use the bad pixel map almost indefinitely.
For extra info on how to create them, I'd advise a look at this video: https://www.astropixelprocessor.com/data-calibration-and-integration-the-pelican-nebula/
At about 2 min, things start with the data.
