> > > This multiplies the whole 4D data by a single scaling factor in order
> > > to make the mean value (over all 4D) equal to a constant value of 1000.
> > Is it possible to turn this of?
> Hi - yes, you can easily turn the grand-mean scaling off by editing
> fsl/tcl/feat.tcl and commenting-out/deleting the line
> set thecommand "$thecommand -I $global_mean"
>
> btw - a minor addendum to Mark's comments on this rescaling:
> "make the mean value (over all 4D) equal to a constant value of 1000"
> in case anyone is worrying - it is the mean of only the non-background
> voxels that is set (and just to be pedantic - set to 10000).
>
> I'm not sure why you would want to turn this off though?
We are analyzing DTI images with Feat (I know what to do with the design
matrix and the issues on pre-whitening to make it valid), and I would like to
see the original FA values.
Thanks,
Erik-Jan Vlieger
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