[OSRS-PROJ] Roussilhe Oblique Stereographic

Gerald Evenden gerald.evenden at verizon.net
Fri Mar 19 21:19:13 EST 2004

A bit stalled on the inverse---part of the problem is that some of the
equations do not make sense and I suspect typos.  As a last resort I
penned an email to the address at the bottom of the reference site
on the off chance he/she can read English.

Reviewed one of the sites suggested earlier (by :Lamparski)

which has even another quasi-stereographic.  Sigh.  This one
is single step and looks vaguely like the Qihe,Snyder,Tobler version.
I said vaguely!  There are a couple of *odd* things about the equations.
One thing about the OST version is that it goes through isometric
latitude rather than conformal latitude.  Isometric is messy as it
behaves like Mercator y and goes infinite as you proceed to the
poles.  Conformal latitude behaves itself nicely.

The Lamparski site is bizarre because latitude is noted as "b" in
the equations for  x-y but it is usually noted "B" everywhere else.  He
uses "b" earlier as minor axis length.

Probably should spend the time to get the original reference but I
am not sure that is what is truly being used by the Poles.

I sent an email to Tobler but I have not received a response.

To paraphrase and old US TV program: "Will the real Roussilhe
Polish Quasi-Stereographic  projection please stand up."
Jerry and the low riders: Daisy Mae and Joshua

PROJ.4 Discussion List
See http://www.remotesensing.org/proj for subscription, unsubscription
and other information.

More information about the Proj mailing list