RASTER Primary raster definition table, listing the fundamental para TrsENTRY Entry or Record Number  I8 ENTRY RAS_ID Raster ID number  I4 Ras DETECTOR Either G for GIS or N for NIS  A3 Det RAS_DESC AFundamental raster description A A65 Fundamental ras SLIT_NUM HSlit number  I5 Slit XSTEP JStep size in the X direction  I6 Xstep YSTEP LStep size in the Y direction  I6 Ystep NX NNumber of X steps  I5 Nx NY PNumber of Y steps  I5 Ny