Best methods for extracting or clipping from mosaic data set?

[DavidMedeiros]

We have a mosaic data set of all ASTER 30m DEM tiles for the world that we frequently need to extract local areas from.

My typical approach to extracting smaller sections from the mosaic file are to either 1) use the mosaic to determine the tile IDs for the study area and then copy just those tiles to a new raster file (mosaic to new raster); or 2) I use an existing polygon to Extract by Mask to get just the portion of the global mosaic that we need.

Extract by Mask is more direct but I've found it's unreliable and only works some of the time for whatever reason. I've tried Clip but if I remember correctly it usually fails when clipping from a mosaic data set. Selecting the tiles always works but is tedious for larger areas and kinda defeats the purpose of having a mosaic.

How can I use the mosaic data set to either automate selection of underlying tiles or to consistently get a good extraction of the mosaic data?

[DavidMedeiros]

Can any one here comment on the use of Clip (Raster) or Extract by Mask for clipping portions of a mosaic in to a new raster?

My reading of the help suggests these shoudl work on a mosaic data set but I always seem to have issue with them.

I just ran an extract by mask using a polygon on and ASTER DEM mosaic and although it completed ok in just a few minutes the resulting DEM was a checker board pattern, not a DEM raster.

[808707]

Have you looked into using raster functions on your mosaic datasets? The function are applied 'on-the'fly'.

You could apply the clip function:

http://resources.arcgis.com/en/help/main/10.1/index.html#/Clip_function/009t00000048000000/

Help file on working with functions is here:

http://resources.arcgis.com/en/help/main/10.1/index.html#//009t00000044000000

Also just thinking have you checked the that the DEM still has the elevation values after processing. It could just be something to do with the way the raster is being symbolised.

[AliciaMein]

Have you figured this out yet.
I have a similar issue.   I would like to use a mosaic dataset and an input selection to clip or mask.
The original data would be to larger to process on it's own?
I would like to use python to do all the processing.
thanks
alicia