UPDATE FROM MABULA
I have had a very rough 2 months unfortunately health wise. I was struck 3x in a row with bacterial infections. The second infection occurred  after a routine hospital checkup and I became very sick. I had to rest and take a lot of antibiotics. Once I was recovering and restarting work 1 month ago, I again became sick. The infection was not yet gone, so even more antibiotics and rest was needed. Needless to say, it took a lot of my energy and I needed a lot of rest.
Finally, the infection is really gone and my energy is coming back step-by-step now and I have started work again. I am terribly sorry to have kept you waiting for support. I will address all outstanding questions and e-mails step-by step and will be on the forum daily from today.
APP 2.0.0-beta47 will come soon as well, a lot of work was already completed before I became very ill, so the release is also nearly ready for you. Beta47 will be much faster actually. Many workflows will be more than 2x faster, mosaics can even be 10x faster than before because registration really received a major boost... all compared to beta46. Â Before I release it, I will make sure that everything is working properly and then I will release it.
With the beautiful comet Neowise gracing our skies these times I've collected a lot of images that each by themselves are a beauty to look at, but will do even better in a timelapse movie.
Is there a way to apply calibration to a series of images and eventually save them in e.g. jpeg format for further processing outside APP?
 Yes, you mean to use APP to calibrate the frames? You can do that and then save the calibrated frames (tab 4 all the way down). Then use e.g. PI for comet alignment.
I want to use APP to calibrate the frames, convert them to TIFF or JPEG or something not FITS that can be read by ffmpeg, and save them automatically. Doing this hundreds of times by hand is not my idea of a fun time 😋Â
Ah, got ya. That will probably be possible when APP gets functionality in processing and calibrating files that are added to a specific folder. This is something that’s going to be added also because of iTelescope automation.