It sometimes happens that there are weird, completely impossible image distortions.
That happens only when using many control points in cases when an ideal set of images is impossible to obtain, eg. due to geometric restrictions.
It would be a great help if there was a possibility to quickly identify such cases…
Could RC please comment if this would be possible at all?
Thanks!
Even better would be if RC would find the obviously erroneus distortions by itself and discard them.
Especially since it ALWAYS works fine after deleting all components and re-running alignment.
I will not give up on this one.
It should be possible by analyzing the distortion grid:
- if the corners are not the image corners - flag!
- if the curvature of opposite sides is asymmetric (above a threshold) - flag!
- if the distortion is X % different from the average distortion of the camera/focal length combination - flag!
good idea 
This is an excellent point.
Götz, do you have any tips for identifying when RC is creating erroneous distortions of this kind, or telltale signs this is happening?
Hi Kevin,
sorry, I never got a notification email for this new post. A flaw of the new forum…
No, unfortunately I don’t have any tips - I browse through all of them “by hand” using left or right arrows on the keyboard, which cycles through the images rapidly and one can usually catch the bad ones. It is a tedious nuisance but then again it doesn’t take hours.
It’s one of those cases that you pointed out once where the machine would be much quicker and better at then the human operator…
@RC: WE REALLY THINK THIS IS IMPORTANT ! ! !