hi, we were going through the logs recently and see something odd during Reduce N/Q/H analysis the log file looks like this: ================================== NQH flips ================================== r_work=0.3047 r_free=0.3518 Analyzing N/Q/H residues for possible flip corrections... segID AL01 renamed chain A for Reduce N/Q/H analysis segID AL02 renamed chain B for Reduce N/Q/H analysis ... segID AL29 renamed chain Y for Reduce N/Q/H analysis segID AL30 renamed chain Z for Reduce N/Q/H analysis segID AL32 renamed chain a for Reduce N/Q/H analysis segID AL33 renamed chain a for Reduce N/Q/H analysis segID AL34 renamed chain b for Reduce N/Q/H analysis segID AL35 renamed chain b for Reduce N/Q/H analysis ... segID BL28 renamed chain z for Reduce N/Q/H analysis segID BL31 renamed chain z for Reduce N/Q/H analysis segID BL13 renamed chain AA for Reduce N/Q/H analysis segID BL29 renamed chain AB for Reduce N/Q/H analysis ... we noticed that the lower case chain letters start to duplicate themselves and are not unique to each segid. when it starts the two letter chain, everything seems unique again. forgive me if that is expected, it just seems kind of strange this was seen in mutlple log files and we are using version Version: 1.8.4 Release tag: 1496 if you need our files or more details, let me know thanks jpd