[Proj] Re: Newbie Polar stereographic question

john star starjohn at hotmail.com
Thu Jul 13 02:13:41 EDT 2006

Hi Gerald!

Thanks, I understand now that in libproj, the plane MUST be orthogonal
to the earth, and there is no support for this plane to be "inside" the

Is there a way to use the library for this case ? by playing with parameters 
what are the rest of parameters like lat_ts and k?), or it is just not 
supported ?

Best Regards

>Basically.  The source point of all the rays is the "antipod" of the point
>of tangency of the projection plane.  That is at a point -lat_0,-lon_0.
I should say lon_0+180
>Thus the ray from the ray source to lat_0, lon_0 passes through the center
>of the earth.  And the plane of the projection is orthogonal to this ray.

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