lower for i in range(1, 32)] * u.keV

        if attenuator:
            base_comps.append(self.components[&#39;attenuator&#39;])

        base = Compound(base_comps)
        base_trans = base.transmission(energies)

        fine = Compound(base_comps + [self.components[&#39;grid_covers&#39;]])
        fine_trans = fine.transmission(energies)

        # TODO need to move to configuration db
        fine_grids = np.array([11, 13, 18, 12, 19, 17]) - 1
        detector_transmission = Table()
        # transmis