Hello, I have two data sets (without cHPI) from each subject, which I want to average together. My plan was first to transform the data into a common space using the 'trans' option of MaxMove, for example: /neuro/bin/util/maxfilter -f data_2.fif -o data2_sss.fif -trans data1.fif -autobad 30 -in 8 -out 3 -ds 4 -format short My problem is that when I open the output (after reaveraging) in xfit, I am told that there is no isotrack data to which I can fit a sphere model. I don't have this problem if I remove the 'trans' parameter. Does the 'trans' option remove any isotrack data? Am I doing something wrong? Sorry if this is a naive question. Any suggestions would be appreciated. Danny