Hi Mark,
thank you very much for your reply.
I have about 20% of phase differences in a given data set that are bigger than 10000.
You were right about the dwell time; the actual number should be 0.32 ms.
When I use the correct dwell time, I start seeing some structure in the undistorted EPI, but it seems that the center of the brain is shifted several mm upwards, whereas lateral non-brain voxels stay in their original place. Is that the global translation you were mentioning?
How do I correct for this given that I am not using fsl_prepare_fieldmap?
Thanks, Caspar
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