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Hi Jess, I have been working with SSEC on incorporation of my GINI ADDE serving mods to the McIDAS core, and we just ran into a somewhat small hiccup that requires some input from someone who knows about the blended TPW products available from the ESPC ftp server, ftp://satepsanone.nesdis.noaa.gov/BLTPW/test/RRdata/ The problem is that the GINI format images available in the BLTPW/test/RRdata directory do not have calibration blocks. In order to add calibration to the images (so that the user can interrogate the images to get PW values that make sense), I need to know the mapping of brightness levels to PW values. I am hoping that you will know someone associated with the creation of the BLTPW images who can lend some guidance on the BRIT -> PW mapping. Just so you know, I did a lot of web searching last evening to see if something had been written about the calibration of the BLTPW imagery. The closest thing I found was a reference to some work done at CSU/CIRA: ftp://ftp.cira.colostate.edu/ftp/Kidder/Static_File/README.txt I downloaded everything from the CIRA FTP site and used it as the basis for the tentative calibration block in the GINI ADDE server code. The problem with doing this directly is that the images that Stan Kidder was talking about in the README.txt file have 75 discrete levels that range from 176 - 251: TPW Files McIDAS Count Data Value(s) -------------------------------------------------------------------- 0 Missing data 1 - 175 Not used 176 - 251 Valid TPW values between 0 and 75 mm (1 mm/count) (values greater than 75 mm are set to 75 mm) 252 - 255 Not used -------------------------------------------------------------------- The GINI images from the ftp.satepsanone.nesdis.noaa.gov site have display values that seem to range from > 108 (the smallest value that I could find is 110) to something greater than or equal to 200. Today's SUNatl images (August 28/12241) do not show display levels higher than 198 for Tropical Storm Isaac. So, the question becomes the following: - is the BRIT -> PW mapping in the BLTPW images this: BRIT PW [mm] 108 0 200 75 - or is it something like: BRIT PW [mm] 108 0 251 75 - or is it something else entirely NB: I list 108 as the minimum display level because it is _by far_ the most common value in all of the images I have downloaded from the ftp.satepsanone.nesdis.noaa.gov site. There is a bit of a rush on finding out the answer to the BRIT -> PW mapping question... SSEC wants to freeze code changes on Sept 1 (in preparation for a v2012.2 addendum?) Thanks in advance for any insight you (or others) can provide! 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: KUC-159541 Department: Support McIDAS Priority: Normal Status: Closed