Setup.preprocessing.vdm_type : (functional_vdm_create only) type of fieldmap sequence files ([]: automatically detect; 1: magnitude+phasediff (or magnitude1+magnitude2+phasediff); 2: real1+imag1+real2+imag2; 3: fieldmapHz)

The above documention indicates I could use 2 magnitude files. However while I trace the running of conn code it appears it just uses the magnitude1 and phasediff file and discarding magnitude2.

As a work around I think I could combine to two magnitude files into a single one before load it to conn. But how should I combine them?

Thanks.