1. A method for locating photomask defects in a universal coordinate system, comprising: writing a test pattern containing a first reference point on a non-productive area of the photomask; mounting the photomask on a first photomask processing machine; initializing the coordinate system of the first photomask processing machine to the first reference point; and determining the location of each of a plurality of defects, wherein the locations are relative to the initialized coordinate system of the first photomask processing machine, and wherein the first reference point is a correlation point for establishing a new coordinate system.