[phenixbb] calculating a phased anomalous difference map for twinned data in phenix.refine

Hi, to confirm the nature of a metal ion in my active site, I want to calculate a phased anomalous difference map in phenix.refine. However my crystals in SG P3(2) are twinned with twin law h,-h-k,-l and a fraction of about 40%. Is there a way to calculate an informative map in phenix.refine in this case? best Michael