Hi Huapeng,
Steve McMullan is right. I had a similar problem a year ago with differences in registration between ArcView and ER Mapper. To make a long story very short, ArcView uses the .TFW file for georeferencing even if the file is a GeoTIFF which contains georeferencing information. Beware if the georeferencing is different between the GeoTIFF header and the .TFW file, particularly if a rotation is used in the latter. In my case, the image that I had received, rather than being reprojected to a 'north up' orientation, was simply respecified using the world file (Steve's last point). In other words, ER Mapper (6.2) used the georeferencing from the GeoTIFF while ArcView used the .TFW and they were not the same. Anyway, I wasted a lot of time trying to figure out what was going on and then trying to reconcile the differences between how the World File and ER Mapper specify and use rotations. In the end, I had to re-register the image myself anyway. Good luck, Gerard Gerard Zaluski, P. Geo. Cameco Corporation 2121 11th Street West SASKATOON, SK Canada S7M 1J3 [EMAIL PROTECTED] 306-956-6359 (fax) 306-956-6390 ----------------------------------------------------------- To make changes to your subscription, please visit our website, http://www.ermapper.com/technicl/ermapperl/index.htm
