[Proj] Terminology for origins

Mikael Rittri Mikael.Rittri at carmenta.com
Mon Oct 6 03:03:31 EDT 2008


Clifford J Mugnier wrote ( http://lists.maptools.org/pipermail/proj/2008-October/003865.html ):
 
> In North Africa, several of the Grids also have a False Northing at the False Origin in order to avoid negative northings.
> Really!
> :-) 
 
Sorry, I don't understand.  In what sense are you using the term "False Origin" here?  
 
If you are using it as EPSG does (at least for Lambert Conformal Conic 2SP 
and Polar Stereographic Variant C), then your statement is not surprising, since 
that's how such a False Origin works: it does have a False Northing and a 
False Easting. 
 
If you are using it in the other sense, as the point where False Easting and False Northing
are both zero, then your statement is contradictory (that's a little too surprising). 
 
So, you must be using the term "False Origin" in some third, more general way.  
Could you give a concrete numerical example? 
 
Best regards,
 
--
Mikael Rittri
Carmenta AB
Box 11354
SE-404 28 Göteborg
Visitors: Sankt Eriksgatan 5
SWEDEN
Tel: +46-31-775 57 37
Mob: +46-703-60 34 07
mikael.rittri at carmenta.com
www.carmenta.com 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.maptools.org/pipermail/proj/attachments/20081006/7d758cc2/attachment.html


More information about the Proj mailing list