Hi,

The '1' in "to3d -time:zt 1 480 3s zero snr*hdr" is not correct
because it should be the numbers of slices in a volume. Even
though your images are stored as 3D volumes, to3d still needs to
know how many slices there are in each of those volumes.

In this case, you seem to have 46 slices in each volume, is that
correct? The reason 0 may work there is because you are letting
to3d figure it out on its own (but then there is no error checking).

I have a separate question regarding your 'zero'. Did you acquire
each entire volume at one point in time? If not, you will want to
inform to3d about the slice timing pattern with which each volume
was created. Otherwise, the slice timing may be off by up to an
entire TR (3 seconds) for some slices.

- rick