MAP_CONVOLUTION

        MAP_CONVOLUTION    Integer

    Select  the  desired  convolution  function for gridding  in  the  UV  plane
    Choices are
            0    Default (currently 5)
            1    Boxcar
            2    Gaussian
            3    Sin(x)/x
            4    Gaussian * Sin(x)/x
            5    Spheroidal
    Spheroidal functions is the optimal choice. So we strongly discourage use of
    any other convolution function, which are here for tests only.