Just noticed now... average drops all spectral data from ti3 files :-( And NO, I didn't use high res spectral mode. I didn't read the chart with -H option. I read that a bug was signaled in the past but it was told that it affected only high res spectral readings, here: //www.freelists.org/post/argyllcms/Average-BUG,1 I do need spectral data for illuminant compensation. Also it looks there's another bug (stupid one). The two averaging ti3 files state explicitely KEYWORD "TARGET_INSTRUMENT" TARGET_INSTRUMENT "GretagMacbeth i1 Pro" while look at the resulting file KEYWORD "TARGET_INSTRUMENT" TARGET_INSTRUMENT "GretagMacbeth Spectrolino" :-D /&