Extract by Mask doesn't obey mask extent

Question

When attempting to extract part of a raster using a separate feature class as the mask the output is not reliably restricted to the mask area. Sometimes the output is confined to a similar shape of the mask, sometimes not at all (i.e. not changing from input raster whatsoever), and sometimes creates an empty raster (but still states it has been succesful). The randomness of output is what's very strange.

I am using ArcMap 10 and both the input raster and mask are in the same coordinate system.

I am also experiencing similar problems with Raster Creation whereby the tool seems not to obey the output extent.

Any ideas as to why this might be happening? Any work-around solutions also appreciated.

Cheers,
James

BrentEdwards · Answer

Another straightforward workaround to try is the Clip_management tool. Since it's outside the Spatial Analyst toolbox, it's going to probably work better with a wider collection of raster input types.

Clip_management has a nice feature: it is set up to snap by default to avoid resampling.

This is definitely the simplest, most straight forward solution. Hopefully some day ESRI will consolidate redundant tools. Unfortunately, in my case, the Clip_management tool at version 9.2 doesn't have the clipping_geometry parameter.

curtvprice · Answer

Another straightforward workaround to try is the Clip_management tool. Since it's outside the Spatial Analyst toolbox, it's going to probably work better with a wider collection of raster input types.

Clip_management has a nice feature: it is set up to snap by default to avoid resampling.

BrentEdwards · Answer

I am having the same problem with the Extract By Mask tool:

http://gis.stackexchange.com/questions/30963/output-raster-extents-when-using-the-spatial-analyst-extract-by-mask-tool-to-cli

As a work around for my use case, I ended up exporting each record in my polygon mask fc to a separate fc to use as the in_mask_data parameter in the Extract By Mask call. This works, but it is frustrating to have to add an intermediate process to workaround the shortcomings (bug?) of the Extract By Mask tool.