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Hello, while refining a structure with NCS, I was re-considering this paper from Michael Chapman's group: Fabiola F, Korostelev A, Chapman MS. Bias in cross-validated free R factors: mitigation of the effects of non-crystallographic symmetry. Acta Crystallogr D Biol Crystallogr. 2006 Mar;62(Pt 3):227-38. In essence, they suggest to exclude from the working set reflections that are (1) related to a test reflection by NCS (2) adjacent to a test reflection and its NCS mates in reciprocal space They have implemented this strategy in a CNS module (R-free2005), but the software is no longer actively supported. Does anybody know if something similar has ever been implemented in other software packages such as phenix? Or am I missing any significant downsides of the approach - apart from a reduction of the working set? Best regards, Oliver ================================================ PD Dr. Oliver H. Weiergräber Institute of Complex Systems ICS-6: Structural Biochemistry Tel.: +49 2461 61-2028 Fax: +49 2461 61-9540 ================================================ ------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------ Forschungszentrum Juelich GmbH 52425 Juelich Sitz der Gesellschaft: Juelich Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498 Vorsitzender des Aufsichtsrats: MinDir Dr. Karl Eugen Huthmacher Geschaeftsfuehrung: Prof. Dr. Achim Bachem (Vorsitzender), Karsten Beneke (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt, Prof. Dr. Sebastian M. Schmidt ------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------