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>From: David Harper <address@hidden> >Organization: NCAR/RAP >Keywords: 200003012325.QAA04248 McIDAS-X GINI netCDF Dave, - back at the comparinson - Since I don't have a way of displaying imagery in netCDF here at Unidata, I decided to compare a couple of LAT,LON pairs from the netCDF file I grabbed from your machine yesterday (GINI0001.nc) with the AREA file copy I made of the same GINI data. I compared the upper left and lower right points of the image by doing an ncdump on the netCDF and a load and interrogation in McIDAS. Here are the quicky comparisons: point netCDF Lat,Lon [deg] McIDAS AREA Lat,Lon [deg] ------------+---------------------+----------------------------- 1,1 36.32418N 110.7891W 36.32222N 110.79055W 800,800 29.71597N 101.4901W 29.71333N 101.49055W You can see that the the Lats and Lons from the upper right and lower left hand corners of the image in AREA and netCDF forms agree to one to two parts in one thousand. This is significantly less than the half a degree offsets that you are seeing. My conclusion from this simple comparison is that the GINI to netCDF conversion is working correctly. The 0.5 degree offset you are seeing must be coming from somewhere else. Tom