Hi I am afraid not. Cheers Saad On 30 May 2014, at 11:20, Jackson Smith <[log in to unmask]<mailto:[log in to unmask]>> wrote: Dear FSLiers, The curvature threshold's range is 0 to 1 in FDT, meaning that the minimum angle between two steps can be no greater than 90 degrees. I would like to try using a minimum angle of greater than 90 degrees – which would require a negative curvature threshold – which is not allowed. Is there another way to do this? Kind regards, Jackson -- Saad Jbabdi University of Oxford, FMRIB Centre JR Hospital, Headington, OX3 9DU, UK (+44)1865-222466 (fax 717) www.ndcn.ox.ac.uk/team/researchers/saad-jbabdi<http://www.ndcn.ox.ac.uk/team/researchers/saad-jbabdi>