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Hi Paul, Sorry for the slow response; I've been working on an abstract that has to be submitted by 5 pm this afternoon... re: examples of use of stretch table in McIDAS > GREAT. > > These are many things I was looking for. I am getting it slowly Very good. re: > A few questions remain however. Ready... re: > First - > > I have displayed an IR image. no stretch tables...just IMAGE enhancement. > > IMGDISP GINIEAST/GE4KIR 2 LAT=35 90 > EU REST IMAGE > MAP VH 14 > BAR > > i then type EU MAKE 0 163 BLACK BLACK > > I expect what happens within that range...but everything else turns to > color! I do not know why! Weird. I just executed exactly what you executed, and did _not_ see the enhancement turn to color. Instead, I got what I expected -- brightness levels 0-163 were set to black. re: > I then type EU MAKE 164 255 BLACK WHITE expecting the levels from 164 255 > to go from black to white which it does but the other colors go to color! This also gave me what I expected. re: > EU TABLE gives me > Brightness Blue Green Red > min max min max min max min max > --- --- --- --- --- --- --- --- > 0 84 0 0 0 0 0 0 > 85 96 130 130 60 60 0 0 > 97 108 200 200 120 120 0 0 > 109 120 0 0 90 90 0 0 > 121 132 0 0 130 130 0 0 > 133 144 0 0 170 170 10 10 > 145 156 0 0 210 210 50 50 > 157 169 0 0 255 255 100 100 > 170 181 0 0 255 255 255 255 > 182 193 0 0 155 155 210 210 > 194 205 0 0 0 0 255 255 > 206 217 0 0 0 0 130 130 > 218 229 255 255 255 255 255 255 > 230 241 150 150 0 0 150 150 > 242 253 255 255 0 0 255 255 > 254 255 255 255 255 255 255 255 This is definitely not the McIDAS image enhancement! re: > I do not where that came from! Me neither. re: > Orignally EU REST gave me the image > enhancement which was correct. > > What is going on? I wish I knew. The only thing I can imagine is that there is something messed up in your environment. Please return the output from the following 4 invocations of the McIDAS DMAP command: <in your McIDAS session> DMAP Frame DMAP FRAMENH DMAP GRAPHICS DMAP TERMCHAR All of the files that begin with these character sequences should be found in a temporary directory under ~/.mctmp. If they are found elsewhere, it means that at some point a McIDAS command was run in an incorrectly setup environment and these files were created in a location other than where they are supposed to be. re: > As I am playing with things more and more, why would I use a SU vs an EU? > > How are they different? A stretch (SU= keyword on an IMGDISP command) controls the mapping of original image values to display values. The H2O.ST stretch table that I used in my previous example caused IMGDISP to only display brightness levels 140-215 and spread them out as 0-255 in the display. The only way for a stretch to be used is by specifying it using the SU= keyword in an IMGDISP command. An enhancement is simply a mapping between display values and colors. Enhancements are associated with frames. One can change the enhancement at any time using the EU (Enhancement Utility) command. Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: IND-391015 Department: Support McIDAS Priority: Normal Status: Closed