Hi,

I'm processing 3T data with 60 direction vectors and 2 images with b-val = 0. Trac-all -prep has been failing at the command:

> mri_convert --frame 0 31 <my_subj>/dmri/dwi.nii.gz <my_subj>/dmri/lowb.nii.gz

> mri_convert: extra argument ("<my_subj>/dmri/lowb.nii.gz")

> type mri_convert -u for usage

Since --frame seems to only want one value, but we have 2 images with low b values. Has anyone encountered this problem before?

Peggy