Hi Rick,
You need to increase the number of steps when you decrease the step size (to get comparable results to the defaults).
In you case I imagine step length=0.1, and number of steps=10000.
Cheers,
Saad.
On 27 Aug 2010, at 01:31, Philipsen, R.H.H.M. wrote:
> Hi,
>
> I'm currently doing some tractography analysis on brain images with voxel dimensions of 0.4x0.4x0.4mm. I've read that the chosen step length should be 1/4 of the voxel dimensions. However, the results I get from with this setting are quite poor. When I increase the step length to 0.3mm, the results are much better.
> My question is, is there a reason why I should use 1/4 of the voxel dimensions? Or are there some papers referring to this?
>
> Thanks,
>
> Rick
>
>
--
Saad Jbabdi
University of Oxford, FMRIB Centre
JR Hospital, Headington, OX3 9DU, UK
(+44)1865-222466 (fax 717)
www.fmrib.ox.ac.uk/~saad
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