There must be a possibility to cope this problem.
You might find two lines running parallel vertical. If you measure the
distance between them in the bottom and in the top you know pretty good
what de distortion is and you might be able to reconstruct the dial on a
piece of paper as if the picture is taken directly in front.
If it was taken a bit from aside, I hope there will be two parallel
horizontal lines in the picture and you can do them same for that distortion.
An other possibility is to print the picture on an overhead sheet and
project it on a surface that you can tilt in such a way that the distortion
is compensated for.
Thibaud Chabot
At 17:15 10-02-2004, you wrote:
One significant problem we have in reverse engineering many of these dials
is that we cannot be sure the original photo was taken straight-on, normal
to the dial face. Many of the photos submitted to John have been shot from
the ground or other accessible vantage point. In orthogonlizing the
images, errors are introduced, because the gnomon and dial face are not in
the same plane. I don't think these can easily be corrected.
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Thibaud Taudin-Chabot
52° 18' 19.85" North, 04° 51' 09.45" East, alt. -4.50 m
home email: [EMAIL PROTECTED]
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