Error: Extract By Mask

[GerasimosDanalatos]

Hello Everyone, 

I am working with a Raster file and one shapefile (Counties of Iowa). I would like to use the function extract by mask for every single county (99). I have tried that via the modelbuilder using an iterator and it does work but, it keeps the size of the raster. As a result, it is 100 times slower and also overloads my C: 

[DuncanHornby]

I've come across this issue before. How I got around it was to run copy feature on the output of the iterator and copy your single polygon to a in_memory workspace, so you have dataset with a single polygon in it. It is then this polygon that feeds into the extract by mask tool. As this is a dataset with a single polygon it takes on the extent of that single feature rather than the whole dataset thus your output raster will have a much smaller extent.