[FRIAM] Simple Trig/Geometry challenge. Win a $50 Amazon card :-)

[Stephen Guerin]

Today at Friam, I showed a small problem I was working on in
photogrammetry. Attached is a Netlogo visualization of the geometry of the
system.

The problem is:  given an image where we know two star coordinates (RA,
DEC), solve for the field of view of the image. We can get the spherical
angle between the stars (alpha) and we know the principal point and two UV
coordinates in the image. These create a right triangle pyramid and I want
to solve for the height X (focal length). Here's a diagram.

[image: rightTrianglePyramid.jpg]
Law of Cosines can get all the interior angles of the bases with S1, S2, S3.



_______________________________________________________________________
Stephen.Guerin at Simtable.com <stephen.guerin at simtable.com>
CEO, https://www.simtable.com <http://www.simtable.com/>
1600 Lena St #D1, Santa Fe, NM 87505
office: (505)995-0206 mobile: (505)577-5828
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