Hi Bob,
I just to make sure we are on the same page when you refer to the residuals(errts), for resting state analysis processed through afni_proc.py. Are you referring to the errts.fananticor+orig which went through despike, slice time, volume registration, anaticor, bandpass filter and smoothed (subject space) prior to warping (I had to warp at a separate stage after afni_proc.py due to abnormal brains).

I used 3dFWHMx -detrend -acf ACF_FILE -mask full_mask+orig -input errts.fanaticor+orig. I created an average value for all three parameters which estimates the smoothness as an overall acf smoothness of 4.2 (which is good because I specified 4.0 mm in my afni_proc.py script).

Thanks,
Ajay