More attempt. This time, the brightness/contrast different between panels seem to reduced. I had used the advanced and multiply-scale options for normalization. I am not sure whether this combination of parameters is responsible for the improvement.
On the other hand, the registration is still terribly wrong. I increased the detected stars to more than 6000. Typical registration rms is between 1 and 3 and number of stars is less than half of the detected stars. For registration, I used dynamic distortion correction and calibrated projective, and no same camera and optics.
One thing I might do is to to pick one unstacked raw frame for each panel and feed them to APP. This way, there should be absolutely no additional distortion introduced by the stacking in PixInsight. (I still do not believe PixInsight had introduced any distortion, but it wouldn’t hurt to test and verify this.) Unfortunately this will have to wait for a couple of weeks.
Cheers,
Wei-Hao
