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Hi Kwan, I have been looking at the MSG data you sent on Sunday. Not being up to speed on using the segmented MSG data files, I had to spend some time looking through the code to see what was happening. Here is what I found: I created the an ADDE dataset with group name MSG as follows: <as 'mcidas', but could be any user> -- copy the files you sent to a directory, I chose /home/mcidas/tmp DSSERVE ADD MSG/VISIR MSGT TYPE=IMAGE DIRFILE=/home/mcidas/tmp/H-000-MSG1__-MSG1 * "MSG segmented images Adding the group MSG as a local dataset Group/Descriptor Type Format & Range RT Comment ------------------------ ----- ------------------ -- -------------------- MSG/VISIR IMAGE MSGT METEOSAT SEGMENTED IMAGES DIRFILE=/home/mcidas/tmp/H-000-MSG1__-MSG1* DSSERVE: done IMGLIST MSG/VISIR Image file directory listing for:MSG/VISIR Pos Satellite/ Date Time Center Band(s) sensor Lat Lon --- ------------- ------------ -------- ---- ---- ------------ 2 METEOSAT8 18 JUL 06199 11:00:00 0 0 1-11 IMGLIST: done IMGLIST MSG/VISIR FORM=ALL Image file directory listing for:MSG/VISIR Pos Satellite/ Date Time Center Res (km) Image_Size sensor Lat Lon Lat Lon --- ------------- ------------ -------- ---- ---- ----- ----- ------------ 1 METEOSAT8 18 JUL 06199 11:00:00 0 0 Band: 1 0.6 um VIS Cloud and Surface Features 3.02 3.00 3712 x 3712 Band: 2 0.8 um VIS Aerosols over Water, Veg 3.02 3.00 3712 x 3712 Band: 3 1.6 um Near IR - Surface, cloud phase 3.02 3.00 3712 x 3712 Band: 4 3.9 um IR Low Cloud/Fog,Fire Detection 3.02 3.00 3712 x 3712 Band: 5 6.2 um IR Upper-level Water Vapor 3.02 3.00 3712 x 3712 Band: 6 7.3 um IR Mid-level Water Vapor 3.02 3.00 3712 x 3712 Band: 7 8.7 um IR Total Water,Cloud Phase,Dust 3.02 3.00 3712 x 3712 Band: 8 9.7 um Ozone 3.02 3.00 3712 x 3712 Band: 9 10.8 um IR Surface/Cloud-top Temp 3.02 3.00 3712 x 3712 Band: 10 12.0 um IR SFC/Cloud Temp, Low-level WV 3.02 3.00 3712 x 3712 Band: 11 13.4 um IR CO2, Cloud Heights 3.02 3.00 3712 x 3712 proj: 0 created: 2006199 110000 memo: MSG data from XRIT type:MSG cal type:RAW offsets: data= 2020 navigation= 256 calibration= 768 auxiliary= 0 doc length: 0 cal length: 0 lev length: 0 PREFIX= 0 valcod: 0 zcor: 1 avg-smp: N start yyddd: 2006199 start time:110000 start scan: 0 lcor: 1 ecor: 1 bytes per pixel: 2 ss: 51 Resolution Factors (base=1): Line= 3.0 Element= 3.0 IMGLIST: done Up to this point, I believe that I have done exactly what you did. Next, I tried displaying the image: IMGDISP MSG/VISIR LAT=0 0 EU=IMAGE BAND=9 Beginning Image Data transfer, bytes= 686020 IMGDISP: loaded frame 17 IMGDISP: done EU: Restoring IMAGE.ET to frame(s)= 17 EU: Done All looks like it should be OK, but it isn't since no image data is displayed. By turning on server tracing when doing an image load, one can see debugging information from the server (if the dataset is local). From this debugging information, I learned that the server was not finding a file it was looking for. I modified the server code, ~mcidas/mcidas2006/src/msgtaget.for, to list out the file it was looking for. I found that it was looking for a segment file that you do not have, the one covering the load point, LATLON=0 0. The segment file you have, turns out to be #2 in a sequence of some number greater than 2. I started guessing Lat,Lons that would be covered until I was able to display the image. The following worked: IMGDISP MSG/VISIR LAT=-30 0 EU=IMAGE BAND=9 MAG=-4 REFRESH='EG;MAP SAT' Beginning Image Data transfer, bytes= 528520 IMGDISP: loaded frame 17 EG;MAP SAT IMGDISP: done EU: Restoring IMAGE.ET to frame(s)= 17 EU: Done Erased graphic frame(s) 17-17 MAP: Completed frame 17 After getting values displayed in the image frame, I was able to determine that the segment you provided in: H-000-MSG1__-MSG1________-IR_108___-000002___-200607181100-__ covers the latitudes of approximately 24:41S to 44:01S. Try loading an image using a centerpoint of -34, 0: IMGDISP MSG/VISIR LAT=-34 0 EU=IMAGE BAND=9 MAG=-4 REFRESH='EG;MAP SAT' and see if you get a valid display like I did. So, it appears that you are missing several of the segments needed for a complete display. Given that your PATH plots were over Europe, I would imagine that you would be needing segments greater than or equal to 5 or so. For reference, the segment number is listed in the file name: H-000-MSG1__-MSG1________-IR_108___-000002___-200607181100-__ ^ segment number After you get all of the segments for the image, you should then be able to use IMGDISP for any point on the disk, and IMGCOPY to write the image into a McIDAS AREA if you want. For instance, after you get all of the segments and put them in the same directory as the other H-000* files, you should be able to do: IMGCOPY MSG/VISIR MYDATA/IMAGES.3000 SIZE=ALL Please let me know if you are able to replicate my findings above. 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: FBA-307750 Department: Support McIDAS Priority: Normal Status: Closed