Extent Issues

[LeighAmmon]

I am trying to get two shapefiles and a raster image that I layer stacked in ERDAS to overlap in Arcmap. I have projected all three into the same projection (WGS_1984_UTM_Zone_17N) but they are not overlapping. I have tried this in ArcMap through the Projection toolbox, in ArcCatalog, and in Erdas with the raster image. I have also tried converting the raster image into a grid and trying to reproject it that way. I also tried to georeference the files. So the extents are off and so are the datum even though the files are of the same section of Florida and are in the same projection. When I input the files into ArcMap all three look like they are different sizes. I am not sure how to fix this and I am at my wits end. Any help wold be greatly appreciated!!

Thanks.

[MelitaKennedy]

I am trying to get two shapefiles and a raster image that I layer stacked in ERDAS to overlap in Arcmap. I have projected all three into the same projection (WGS_1984_UTM_Zone_17N) but they are not overlapping. I have tried this in ArcMap through the Projection toolbox, in ArcCatalog, and in Erdas with the raster image. I have also tried converting the raster image into a grid and trying to reproject it that way. I also tried to georeference the files. So the extents are off and so are the datum even though the files are of the same section of Florida and are in the same projection. When I input the files into ArcMap all three look like they are different sizes. I am not sure how to fix this and I am at my wits end. Any help wold be greatly appreciated!!

Thanks.

ArcMap is likely reading any internal georeferencing/coordinate system information for the rasters. If they have different extents, they're almost certainly georeferenced to different coordinate systems. Redefining the information (using data property page in Catalog or the Define Projection tool) just updates the metadata, not the actual data extents or coordinate values.

For US data, you could have a layer using a state plane zone instead (if the relative size is off 3x, could be feet vs meters) or one in geographic (decimal degrees). You're going to have to figure out the 'native' coordinate systems of the data, or georeference, then define the coordinate system to what you used for the georeferencing. But georeferencing should be a final can't-figure-it-out-otherwise step.

What extents are you seeing (check each layer individually in ArcCatalog or a new ArcMap session) and what general location/area do the different layers represent?

Melita