[magick-users] Pinbarrel distortion correction

[Wolfgang Hugemann]

Anthony and Fred,

I have tested a few tools that claimed to determine the correct 
distortion correction coefficients for a certain camera type, but could 
not find one that did the job reliably. Some of them used specific test 
images of a special target (like equally spaced lines) that had to be 
photographed.

This really complicates the process of calibrating a certain camera 
type, as these target have to be quite large in order to be photographed 
from some distance. Thus I think that the approach taken by PTlens is 
much more promising, i.e. using modern architecture buildings as 
ready-made targets. Anyway, I would like to know which programm you were 
referring to, Anthony, in order to give it a try.

So far, I didn't know that this distortion has already been implemented 
in IM, so thanks for the hint. But as I said, as long as we do not have 
a reliable tool to determine the parameters of a certain camera type, 
this program option is rather academic.

I will try to work out the approach in somewhat more detail, applying it 
to a real test photograph and then come back on the subject again. This 
will hopefully be a matter of a few days...

Wolfgang