Dear FSL,
I am a bit confused about ddy_correct. My diffusion data is a single file that contains multiple diffusion-weighted images. I pick the 0'th image (b=0) as the 'reference volume'. As I understand, all the other volumes are affine registered to this volume. However, when I look at the .ecclog file, the affine transformation matrix for the reference volume is not an identity matrix. It contains some elements of shear/translation/rotation etc. If it was the reference volume, it should not have been transformed. When I compare the image intensities there are slight differences to the original confirming that the transformation was applied to the reference volume.
Please help, thanks.
Chris
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