Wild-type Columbia (black circles), atpc2 (open squares), gamera (gray triangles), and dpa1 is complemented with 35S∷ATPC1 (open diamond) were compared for differences in actinic light intensity-dependence of LEF (A), energy-dependent exciton quenching (qE) (B), light-induced pmf (estimated by analysis of the electrochromic shift (ECSt) (C), and proton conductivity across the thylakoid membrane (gH+) (D), based on ECS decay kinetics. Data is for attached leaves (n = 3–4).