notebook with photometric data

Date1987

Inventory Number2004-1-0214d

ClassificationNotebook

Subject

Maker Edwin H. Land 1909 - 1991

Cultural Region

Place of Origin

Dimensions8 x 29 x 30 cm (3 1/8 x 11 7/16 x 11 13/16 in.)

Material

DescriptionTogether with 2004-1-0214e and f, this binder is filled with spectrophotometer plots dated from June 1987 to December 1987. Data come from the Spectra Pritchard Photometer, 2004-1-0214a and from a computer algorithm. There are usually three types of graphs called "numerator", "denominator" and "designator". The designator graph is the result of a calculation from a special algorithm based on the other two graphs. The first two graphs are the "physical" data as perceived by the photometer. The designator graph represents the Retinex model of color perception as the brain would see it. The designator, therefore, is a calculation based on a model of perception, Retinex, which got more refined over the years. The designator graph is different from the other two "real" (in physics' terms) color graphs because it is designed to illustrate how color is perceived by the brain.

Some of the data in the binders also come from Mach bands experiments, which were done, for instance, with 2004-1-0115.

In Collection(s)

Signedunsigned

Curatorial RemarksThis notebook is now located in the CHSI library, C4-I drawer 1.

FunctionUsed by Land for his experiments with color vision (Retinex theory).

ProvenanceThis object belonged to Edwin H. Land and came from the Rowland Institute, Harvard University. Gift of the Edwin H. Land Family.