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Hi Robert, This note is a quick update on the progress of using the LEO command with polar orbiter data from the PLR dataset on SATEPSDIST4E.NESDIS.NOAA.GOV: I have been talking with Russ Dengel about how to use LEO in the context of the PLR dataset images. It turns out that LEO uses NAVCALC which, in turn, access NAV datasets in one of its options. Both Russ and I played around with NAVCALC yesterday, and it became immediately obvious that the LOS or VIEW options of NAVCALC rely on the most recent image available in a dataset. Since this is not what is desired (one can not project orbital passes into the past), Russ volunteered to investigate updating LEO. Here is a snippit from one of his emails: "I just sent a note to Brian covering what we talked about. I then went to Santek and asked about the NAVCALC command. Turns out that we really want to use the 3rd option (TLE) navigation. Its easy to get (just an ftp from a web source directly into a local text file which can be accessed by ADDE. These files hold navigational elements for all current Polar platforms and the navigation can be projected forward and backwards in time. The image dataset option that we were trying to use ONLY works for the latest image. I try to re-rig LEO to use TLE instead of NAV datasets." The Brian Russ is referring to is Brian Hughes of NOAA/ESPC. I suggested that Russ/SSEC get access to the ESPC server that is hosting the PLR data mainly so we could both test using the same data. So, Russ is now looking into upgrading LEO to be able to use TLE navigation datasets -- he seemed pretty confident that this should work. If/when he gets the code working, he will send me the updated source, and I will roll it into a Unidata McIDAS addendum. Stay tuned... 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: QRJ-934735 Department: Support McIDAS Priority: Normal Status: Closed