Science

Rood was one of the first to suggest using the concept of photography in microsopes, and one of the first to take binocular pictures with that instrument.   His methods of photometry that he has created, and his examination of occurance that depend on the physiology of vision, were very clever, as well as his ideas on color contrast.

"When we gaze at a surface that fluctuates not too rapidly in

brightness, there is a sense of flickering, and the same is true

when two surfaces differing in brightness are alternately presented

to our field of view. If now the illumination of the two

surfaces be gradually equalized, the flickering will diminish and

will disappear at equality. This is obvious when we have similar

surfaces as to color illuminated by the same quality of light and

it forms a criterion quite independent of brightness that may be

used in photometry." Ogden Rood