25-08-2010: While the ASCII Grid format is very useful for small downloads, it may fail for large raster datasets may fail. The ASCII grids format can create very large files. If you are downloading one of the 25m DEM grids for example, the whole layer may generate an ASCII file in the order of 20 Gb. We recommend you use the GeoTiff option in such cases. We will be looking at options for limiting ASCII Grid downloads to a maximum file size and/or alternative file formats.
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