Demonstration of red/white projections and rod-Lcone color

In the late 1950's Edwin Land, while developing instant color film, repeated James Clerk Maxwell's 1861 three-color projection experiments. By accident, a two-color red and white projection appeared on the screen. Fascinated by the multicolored images that he saw, Land studied the phenomena extensively, published a series of papers and developed with Texas Instruments, a prototype red and white television system. This talk will demonstrate Land's original Red and White projections using equipment on loan from the Rowland Institute. In the late 1960s and early 70s McKee, Benton and McCann investigated color images from stimuli that excited only rods and long-wave (L) cones. They used dark adaptation curves, flicker-fusion rates, the Stiles-Crawford Effect, and apparent sharpness to differentiate rod and M/S-cone responses. They showed that color from rods and L cones under the right stimulus conditions was nearly identical to cone-cone color. This talk will also demonstrate color from rod -L cone interactions.