I’m trying to create a warp field between two EPI’s scanned in opposite directions, using the plusminus procedure of 3dQwarp. However, I have noticed that it always forces the axes tilt to be plumb, and interpolating data to do so. I am trying to make sure that this does NOT happen, as I am building a pipeline where my functional data is touched as little as possible. Is there a way to tell 3dQwarp to leave the obliqueness of my data alone? If not, is there an alternate way of computing the warp field that serves my purposes?
Thanks in advance,