OpenLayers defaults to EPSG:4326, so if you leave the projection empty in the map options, your map will be EPSG:4326. You cannot overlay a topo layer that is in EPSG:4326 onto OSM, which is EPSG:900913. If your topo layer is a WMS, it may also be available in EPSG:900913. If it is a vector layer, you could transform from 4326 -> 900913.
----- Bryan McBride, GISP OpenGeo - http://opengeo.org Expert service straight from the developers. -- View this message in context: http://osgeo-org.1803224.n2.nabble.com/using-two-Projections-tp6352040p6352071.html Sent from the OpenLayers Users mailing list archive at Nabble.com. _______________________________________________ Users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/openlayers-users
