Following on from <a href="http://equal-area-maps.com/" target="_blank">equal-area-maps.com</a>,
I am putting together some samples for polar projections. Eventually
I'll publish a couple of articles at GeoWebGuru.com. I'm still at the
survey stage, but it looks like there are two stereographic
projections: "stere" and "sterea" and it isn't clear what the
difference is.<br>
<br>The Proj.4 documenation doesn't mention the "sterea" projection,
but pages found by Google suggest it is a recent alternative addition?<br>This would explain its absence from the original Snyder documentation and addenda.<br>
<br>The best description I have found is on the GeoTIFF site which says
that they are two different but valid approaches, with "stere" being
the original (Snyder) approach. However it notes that the two
approaches produce different results away from the centre! To me this
suggests that it is unlikely that are both are equally valid.<br>
<br>Considering both were ported to Proj4JS, I assume this issue has already come up? <br>What does "sterea" offer over "stere", and which is usually recommended?<br><br>Best regards,<br><font color="#888888"><br>
Richard Marsden<br>
Winwaed Software Technology LLC<br><a href="http://www.winwaed.com/" target="_blank">http://www.winwaed.com</a><br><a href="http://www.mapping-tools.com/" target="_blank">http://www.mapping-tools.com</a><br><a href="http://www.geowebguru.com/" target="_blank">http://www.geowebguru.com</a><br>
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