Latest Contributions by DavidBailey

Hello all,   I am working on a land cover change analysis; I recently created a canopy cover raster with the following projection info:   NAD_1927_UTM_Zone_11N WKID: 26711 Authority: EPSG     Projection: Transverse_Mercator False_Easting: 500000.0 False_Northing: 0.0 Central_Meridian: -117.0 Scale_Factor: 0.9996 Latitude_Of_Origin: 0.0 Linear Unit: Meter (1.0)     Geographic Coordinate System: GCS_North_American_1927 Angular Unit: Degree (0.0174532925199433) Prime Meridian: Greenwich (0.0) Datum: D_North_American_1927   Spheroid: Clarke_1866     Semimajor Axis: 6378206.4     Semiminor Axis: 6356583.799998981     Inverse Flattening: 294.9786982   I received LIDAR-derived DSM's and DTM's for the same area but from a later year with the following projection info:   WGS_84_UTM_zone_11N Authority: Custom     Projection: Transverse_Mercator false_easting: 500000.0 false_northing: 0.0 central_meridian: -117.0 scale_factor: 0.9996 latitude_of_origin: 0.0 Linear Unit: Meter (1.0)     Geographic Coordinate System: GCS_WGS_1984 Angular Unit: Degree (0.0174532925199433) Prime Meridian: Greenwich (0.0) Datum: D_WGS_1984   Spheroid: WGS_1984     Semimajor Axis: 6378137.0     Semiminor Axis: 6356752.314245179     Inverse Flattening: 298.257223563   When I imported the new DTM's and DSM's, the layers were slightly off (by about 80 meters or so). I edited the spatial reference information in ArcCatalog and the layers still did not match up. I used the Project Raster tool and the layers still did not match up. I used the Define Projection tool and the layers still did not match up.   Any ideas on why these two datasets are not matching up? What should I do?   Thanks! David ... View more