[OSM-newbies] Incorrect scale or longitude when exporting maps?
osm-list at deelkar.net
Mon Jun 30 12:10:07 BST 2008
luke.angel at clipsal.com.au schrieb:
> The scale of the images seem proportional so it seems to me that the
> longitude values for the images must be incorrect. How can the width of
> both exported images equal 1.61 degrees of longitude when one image is
> 22.3 degrees further North than the other?
The scale factor used is the one of mapnik IIRC which has no correction
for latitude. so there is only one latitude where the scale factor is
"correct", I assume this to be the equator, but for a real scale factor
to work you'd need information about the resolution your image is later
displayed in, so take this only as a rough estimate of your scale.
Dirk-Lüder "Deelkar" Kreie
Bremen - 53.0952°N 8.8652°E
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