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>From: "Paul L. Sirvatka" <address@hidden> >Organization: College of DuPage >Keywords: 200210041733.g94HXZ106826 McIDAS NEXRCOMP BAR IMGREMAP IMGCHA Hi Paul, I will restate the objective of your endeavor as I understand it, and give you my approach. You want to remap a NEXRCOMP 1 km national base reflectivity composite radar image into the projection of some other image. You want to suppress echos in the remapped image that are less than 5 dBz. Finally, you want to put up a data bar that reflects the echos that are visible. Here is my approach: 1) remap a NEXRCOMP/1KN0R-NAT composite base reflectivity image into a GOES-East projection (you have already done this, I just want to be complete): IMGCOPY RTIMAGES/GE-IR MYDATA/IMAGES.1234 SIZE=ALL IMGREMAP NEXRCOMP/1KN0R-NAT MYDATA/IMAGES.1234 SSIZE=ALL 2) display the remapped image IMGDISP MYDATA/IMAGES.1234 EU=BREF24 This will result in a display that still shows echos below 5 dBz. 3) create an enhancement that suppresses echos below 5 dBz. EU MAKE 0 85 BLACK EU SAVE MYBREF I came up with this by examining brighness levels in the displayed image. It seemed that brightness levels of 85 and below represented the echos you do not want to show. After you have created the desired enhancement, you could load all succeeding images using it: IMGDISP MYDATA/IMAGES.1234 EU=MYBREF 4) create a stretch table that correctly shows the relationship between echo that range from 5 to 75 dBz and brightness levels that range from 85 to 255: SU INI MYBREF NIDS ECHO SU MAKE MYBREF 5 75 85 255 5) use BAR to put up a data bar on the image: BAR SU=MYBREF Please let me know if this is not what you had in mind. Tom