Fig. 1
Representative On–Off series ERG tracings with a range of background luminances. In each instance responses to 2.5, 25, 180, 500 and 1,250 cd/m2 stimuli presented for 250 ms are shown (red line above tracing indicates duration of stimulus). A responses with 0 (no background) and 0.01 cd/m2 background. B responses with 0.1 and 1 cd/m2 background. The small b-wave superimposed on a longer negative deflection is denoted by arrows in the 1 cd/m2 background. C responses to 10 and 42 cd/m2 background. Note the amplitude scale difference between the three panels