Facing problem with CBF scale in perfusion_calib map generated after CBF estimation as per BASIL tutorial. ASL was acquired using pcASL with single delay 1s and control image. I skipped step 1 as machine output was subtracted image and directly applied kinetic inversion model as well as estimated CBF. Output of CBF estimation is perfusion_calib with perfusion ranging from 700-2400 while example data from FSl website shows CBF ranging from 0-20.

I have attached perfusion_calib map. 

Please help.
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