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Hi > Full Name: Seiradakis Kostas > Email Address: address@hidden > Organization: Technical University of Crete (Greece) > Package Version: IDV: 2.5, Java: build 1.6.0_10-b33 > Operating System: Windows Vista > Hardware: > Description of problem: Happy new year. > > > The problem that I have with IDV is that when I plot mean sea level pressure > (grib files from UCAR, ds090.1) contours sometimes were not plotted right > (attached image 1.jpg). In this image I used contour interval 2 millibars. > When I used the default selection (contours interval 4) plotting works fine > (also the same problme occurs when i use contours interval 3). If I used the > default selection it is not very helpful because the contour's labels are > very sparse(attached image 2.jpg). Any ideas? The problem is that when you plot the data in a projection other than the native data projection, the IDV tries to account for lines that cross the projection seam. In this case, it is not doing it very well when you select a lower contour interval. When you plot the contours at 2 millibars and get the spurious lines, bring up the Display Control's properties dialog (Edit->Properties on the Display Control window). Check the Use Fast Rendering checkbox and click OK. If that clears up the issue, then you can set the global Use Fast Rendering option from the Edit->Preferences dialog under the General Tab. See the following sections of the User's Guide for more information: Known Problems: http://www.unidata.ucar.edu/software/IDV/docs/userguide/Bugs.html#dataprojection FAQ: http://www.unidata.ucar.edu/software/IDV/docs/userguide/Faq.html#fastrender Don Murray Ticket Details =================== Ticket ID: GZK-241264 Department: Support IDV Priority: Normal Status: Open