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Hi Richard, re: which version of McIDAS are you looking at using > Not entirely sure but since we do not currently use the McIDAS > legacy software I suppose we'd want the newer version. I am > downloading it now for a look. Very good. Code was added to McIDAS-V to be able to use METEOSAT imagery in its wavelet compressed form. This may be just what you are looking for. re: which bands were you interested in resolution for? > I was talking about the lower resolution channels. I have read that > they have a 3km resolution but out here in Qatar, right on the edge > of the image, the resolution when projected to lat/lon seems a lot > lower (even as low as 6-7km). Since many authors report 3km resolution > regardless of location I was wondering if I am missing something. People typically quote the resolution at the sub-satellite point. I referred to this as the nominal resolution: 3 km for the IR channels and 1 km for the high resolution VIS channel. You are correct in your comment that the resolution at a specific location will be worse than that directly under the satellite. For instance, I just created a band 9 (10.8 um) image sector from METEOSAT 10 centered on Qatar (25N, 51E), and I see that the resolution at the center of this sector (which will be at 25N, 51E) is 4.62x6.39 km. re: Spatial resolution can not be improved from its original form. > Thanks. We were wondering if the high-res channel is somehow used > (fused?) to simulate higher res No, it is not. re: > It seems that EUMETSAT provide images in 'native' format (.nat > extension). I am not familiar with the format of files with .nat extension. The wavelet compressed form I referred to earlier is the format that would be on disk as a result of receipt/procesing by a EUMETSAT satellite ingestor (the format of the data in EUMETCAST is (or at least was) wavelet compressed). re: > There seems to be few software that read this (we tried > ENVI and ArcGIS which didn't read the image and ultimately Quantum > GIS that did though clunkily (through functionality of GDAL libraries)). Hmm... I wouldn't imagine that Quantum GIS would know about the wavelet compressed format used in EUMETCAST broadcast, but I could be wrong. re: > Given the hassles I have had to make sense of this data I think there > is a real need for something like McIDAS OK. > I am looking forward to downloading McIDAS and trying it out. I assume from the comment made at the beginning of this email that you are in the process of testing out use of McIDAS-V (which you would have downloaded from UW/SSEC, not Unidata). re: > Thanks again for your prompt and informative reply. You have really helped us. No worries. 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: HCT-951994 Department: Support McIDAS Priority: Normal Status: Closed