Fieldmap correction gone wrong

[jsein]

Please try fmriprep v23.0.2 where a fix may have solved this issue:

Image orientation and PE direction for fMRIPrep

I had assumed they were reversed because the phase encoding direction given in the json file for the fmap is opposite (i.e. i vs i-), For phase-difference fieldmaps, that does seem likely to produce a sign-inverted estimate of the field, which would then lead to incorrectly expanding/contracting when applying correction. We’re using fMRIPrep 20.2.7 as advised here after we were having issues with SDC in v22 If you wouldn’t mind trying out 23.0.2 for the fieldmaps that are working well, I …