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Hi, I am trying to unwarp some fMRI data from a Siemens Allegra scanner using a gre_field_mapping sequence and need to prepare the field map. The intensity values for the reconstructed phase image range from 0 to 4094, and the TEs were 4.88 ms and 7.34 ms, so from what I gather from other posts, I should do: fslmaths [phase_input] -sub 2047 -mul 3.14159 -div 2047 -div .00246 [radians_per_sec_output] such that the final range is -1277 to 1277 (and mask with the skull stripped magnitude image). And I should be able to input this into fugue right? Also, is there a way to adjust the registration in the b0 unwarp option in FEAT so that it does no search? My data has very few slices in the z dimension, but all my data is practically aligned already (fieldmap, epi, matched bandwidth and a structural scan). When I use the b0 unwarp option, it reorients the data in the wrong direction when matching the fieldmap to the epi. Using 'no search' in the registration step always works to align the epi to the matched bandwidth to the hi res structural, so I assume it would be helpful if I could include no search for the fieldmap somehow as well. thanks a lot, Kyle Kern