Light and Colour Theories, and their relation to light and colour standardization

by Joseph W. Lovibond

The colour is a yellow green in the proportions of 7·0 of yellow, to 0·5 of green, and 1·5 brighter than the standards.

Every daylight colour being thus measurable by a suitable combination of standard glasses, with or without the addition of a Light, or a Neutral Tint factor, it follows that any colour can be described both qualitatively, and quantitatively, in terms of the colour sensations yielded by the standard glasses and their combination. The distinct colour sensations are those, which, by common consent are known as Red, Yellow, Blue, Orange, Green and Violet, and they are yielded by single glasses, or by pairs as already described; all colours therefore fall into the following categories:—

A.—Single colour sensations:—

1. Transmitted by single glass standards:

Red.
Yellow.
Blue.

2. Transmitted by equivalent pairs of standard glasses:

Orange.
Green.
Violet.

B.—Double colour sensations transmitted by unequal pairs of standard glasses.

Red orange, transmitted by unequal units of red and yellow, red preponderating.