[OSRS-PROJ] Schreiber Transverse Mercator

[Gerald Evenden]

After shelving the Roussilhe for the moment I shifted back to trying to 
find more
information on the even more elusive Schreiber Transverse Mercator 
projection.
While googling thought a desperate selection choice and 8,000 results I 
hit
upon  GPSmanhttp://www.ncc.up.pt/~mig/gpsman.html wherein lay a tcl
procedure to "Schreiber Stereographic."

This turned out to be the same as libproj4's +sterea (Alternate 
Stereographic)
projection which is a double conversion through the Gauss sphere.  I 
could
not pin down the creators source for the name but it seems to indicate 
that
Schreiber had a thing for the double conversion and may have applied it 
to
the Transverse Mercator problem as well.  Snyder in "Flattening the 
World"
describes the Schreiber as a double conversion.

The next release of libproj4 will contain the "stmerc" projection 
tentatively
called the Schreiber Transverse Mercator.  As Snyder indicated, the 
scale
error is not zero along the central meridian but from what I find, 
follows a
rather bizarre path.

_____________________________________
Jerry and the low riders: Daisy Mae and Joshua

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