The help file already tells you that the sum of the flux in the CC file will be scaled by the SU table flux. As of tomorrow, it will reset the scaling factor to 1.0 if it is zero. => if you do not know the total flux, better leave it 0 in the SU table and let the CCs define it. Putting 1.0 in the SU scales the CC flux to 1.0 Jy. Eric