Am 11.09.2019 um 14:23 schrieb Michael Koch:
Am 11.09.2019 um 13:13 schrieb Michael Koch:
Paul,
I think the field of view isn't correct in the stereographic output.
Here is a script for making really nice test images, for measuring
field
of view:
Well spotted, thanks, should be fixed.
The field of view of the stereographic output isn't correct. Here are
a few examples:
set in command line / measured in output image
60° / 74°
120° / 135°
180° / 180°
240° / 212°
300° / 236°
360° / 274°
Make this correction:
new_fov = 180 * tan(fov/4)
where fov the the field of view you get from the command line, and
fov_new is the value that you use for the filter.
You must exclude values too close to 360°, because 360° stereographic
projection is impossible.
P.S. of course fov must be converted to radians before using tan():
new_fov = 180 * tan(fov * pi / 720)
Michael
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