For maps that are non-square (e.g. M51) there was a bug in the gridder when x_extent > y_extend. This was fixed on Dec 28, but now I get the impression that the keywords for x_extend and y_extend have the reverse meaning.
It should be noted that the layout of the grid is odd in that X and Y are swapped. The X is processed reverse as well (since cdelt1 is positive in the template grid?). All very confusing (to me).
The best is take a square grid big enough to keep all the data, but this is something that should be fixed/clarified.
For maps that are non-square (e.g. M51) there was a bug in the gridder when x_extent > y_extend. This was fixed on Dec 28, but now I get the impression that the keywords for x_extend and y_extend have the reverse meaning. It should be noted that the layout of the grid is odd in that X and Y are swapped. The X is processed reverse as well (since cdelt1 is positive in the template grid?). All very confusing (to me).
The best is take a square grid big enough to keep all the data, but this is something that should be fixed/clarified.