Hi All, We're running a connectivity analysis with 110 subjects, and the first step our software undertakes is to create a mask that is the overlap of all subject maps (first volume of their run). Unfortunately, one of these subs is misaligned and needs to be purged. I would like to avoid looking through each one individually. I attempted some scripts that would run an imcalc of 'i1+i2...i10' (ten subs at a time) to just narrow down the suspects; also tried 'i1&i2...&i10' hoping this would create the same overlap map that MarsBar does. Any bright ideas out there? I would be much obliged. Thanks, James