[FieldTrip] question on the coordinate

[qi li]

Hi there,

Our MRI data was already alined to Talariach coordinate. Let me call it mri.

I aligned the MRI coordinate to MEG by ft_volumerealign and produce a
variable called mri_other.

mri_other=ft_volumerealign(cfg,mri);

Now I reslice by
mrirs=ft_volumereslice(cfg,mri_other)
and do segmentation by
cfg.coordsys='ctf;
seg=ft_volumesegment(cfg,mrirs);

I found mrirs.transform is not equal to mri_other.transform. Is this
correct? I think re-slicing and segmentation should not change the
transformation matrix.

The last question is since our mri data was already aligned to
Talariach, do we need to realign segmented?

Thank you all!
Qi