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>From: Robert Mullenax <address@hidden> >Organization: UCAR/Unidata >Keywords: 200107251752.f6PHq0121808 >Steve, > >I have tried several things and none seem to work. I just tried >a VIS sat image and used lutfil=visgray.tbl. I get a white >background with a few specs of black and then the echos. >It almost looks like a negative image. > >I also tried making a vgf file from the NEXRAD composites >using gdplot2. It seems to make them okay but when the >result is viewed with NMAP2 or in a script it only >produced output for a small part of the country..in this >case the southeastern U.S. I had GAREA for the entire U.S >Is there a file size limit for vgfiles? > >Thanks for your help on this. >Robert > Robert, LUTFIL=default or GRAY works for me. Generally, if you get something that looks negative, then you have a raw area file (no calibration block), so the data is 0-32769 but all your color values are in the range 0-255. Our IDD imagery in McIDAS area files works here- I tried a 4km GOES-8/IR. Are you using the area files from the IDD data stream at NSBF? Steve Chiswell