For the PC-TEA-sulfite system I developed Delta 100 in PC-TEA 1:100 with added sulfite 0,10,30,70 g/L 17.5min 68F as noted in a previous thread.Sulfite slightly raised the pH to 9.5,but if there was any superadditive effect it was not detected as all the negatives taken at the same EI have the same density by visual observation.