def create_mask(im,head):
    """ Create the mask using the image and the
        saturation level set in the header
    """
    # Create the mask
    #  mask=1   bad
    #  mask=0   good
    try:
        saturate = head['saturate']
    except:
        saturate = 60000.0
    mask = im > 0.9*saturate
    return mask