Hello all, I hope someone can help me out with this issue...  I am trying to plot satellite data over Europe and am resizing the data using the CONGRID function and then interpolating it to make it display correctly... except it is not.  When I display the data I get these lines of misplaced data which seem to line up exactly along longitude lines and appear to be removed from the right most side of the image and placed at even intervals.  I had a hunch and removed all the columns of data to the west of and including the Greenwich Meridian and the lines go away.  The problem also goes away when I do not interpolate the image, but then if I want to move to smaller scales, like of a single country, the pixels are all separated.  Am I missing something that IDL requires when interpolating an image with CONGRID that includes data around the Greenwich Meridian? EDIT: It should also be noted that I convert the longitudes to negative values west of the meridian. Thanks for your help! -Chris