[GRASSLIST:5050] Re: difficulties with i.ortho.photo
rich at greenwoodmap.com
Sun Nov 24 18:24:39 EST 2002
>When i register a camera, what is this "point of symmetry" that i have to
>locate on the photo ?
It is something that is determined in the camera calibration. The
photogrammetrist should be able to give you a calibration report for the
camera, but if you don't know, assume 0,0. It's the center of the image.
>What is the origin and direction of X and Y on the photo ?
The origin is the center of the image (or the point of symetry) and X and Y
are left-right and up-down.
My fiducial marks look something like this:
106 -106 lower right corner
-106 -106 lower left corner
-106 106 upper left corner
106 106 upper right corner
0 112 bottom middle
-112 0 left middle
0 112 top middle
112 0 right middle
Richard W. Greenwood, PLS
Rich at GreenwoodMap.com
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