The barshadow step has the following optional arguments.
--inverse(boolean, default=False)- A flag to indicate whether the math operations used to apply the correction should be inverted (i.e. multiply the correction into the science data, instead of the usual division).
--source_type(string, default=None)- Force the processing to use the given source type (POINT, EXTENDED), instead of using the information contained in the input data.