[Proj] Ellipsoidal Orthographic

Noel Zinn (cc) ndzinn at comcast.net
Tue Jun 28 06:43:47 EST 2011

The only equations for the ellipsoidal orthographic that I've ever found 
published (in a book or journal) are those of Bugayevskiy and Snyder (1995), 
which are complicated and (the authors acknowledge) truncated.  Following 
EPSG Guidance Note 7, Part 2, I've prepared a presentation on the 
ellipsoidal orthographic that offers simple, exact equations.  The 
derivation also suggests that the ellipsoidal orthographic is unique among 
projections, being transitional between distorted cartography in 2D and 
undistorted visualization in 3D on a computer in ECEF or ENU (topocentric) 
coordinates.  A link to the presentation follows:


Does anyone in this group have other sources of information on the 
ellipsoidal orthographic?


PS - Scroll the page if it presents in black

Noel Zinn, Principal, Hydrometronics LLC
+1-832-539-1472 (office), +1-281-221-0051 (cell)
noel.zinn at hydrometronics.com (email)
http://www.hydrometronics.com (website)

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