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I am trying to clip a raster (DEM) with a polygon layer in ArcGIS10.1, using Data Management>>Raster>>Clip. Basically the clipped raster has many pixels outside the polygon boundary, mainly for thin polygons (about 1 pixel wide) or ones with sharp corners. I have different versions of the original raster, all with 25m cell size (but slightly different outline extent), andwhen I clip them I get slightly different results. (I would expect one or two pixels, but this seems like too much). I'm a fairly new GIS user, and I suspect the problem is something with my environment settings, but I've tried with 'snap to raster' both on and off, and the problem persists. I have to calculate zonal statistics on the clipped raster, and the area calculation shows that the clipped area is not the same (or even close sometimes) as the original polygon. Has anyone encountered this problem or have suggestions to fix it?

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I haven't had the problem, so I am not providing an answer, just a resource for possible alternatives: blogs.esri.com/esri/arcgis/2011/10/05/… –  Barrett May 15 '13 at 13:01
    
Thanks. I just tried the Extract by mask tool, and it works better, keeping the extracted raster within the polygon outline. I learned from other posts and the ESRI site that these tools do the same thing (clip and extract), but clearly the result is not the same. –  Liz S May 15 '13 at 14:11
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