@PixLab, thanks for the tip. In the case I described, two or more photos taken handhold have another POV. When one take one or multiple photos without the camera mounted on a tripod, but from the same spot, the position of the camera move slightly in space because the one who is holding the camera can not stand in a 'frozen' position(specially when it's freezing cold...). The little difference in point of view results in a slightly different perspective and minor lens distortion. The distortion of perspective can be corrected with the plugin from Ottia Tuota. The lens distortion is in this case negligible.
Example, not really what this post is all about, but explains the perspective difference (and other things) :
https://www.researchgate.net/figure/Two-..._221516190
Test with the difference layer :
With the first layer difference on two not perspective aligned photos (aligned manual):
With the first layer difference on two perspective aligned photos :
There are more white lines visible on the not perspective aligned photos : more perspective distortion.
Example, not really what this post is all about, but explains the perspective difference (and other things) :
https://www.researchgate.net/figure/Two-..._221516190
Test with the difference layer :
With the first layer difference on two not perspective aligned photos (aligned manual):
With the first layer difference on two perspective aligned photos :
There are more white lines visible on the not perspective aligned photos : more perspective distortion.