Abstract

Quantitative spectrographic analysis is based upon the theory that the light emitted by an element is a function of the quantity of element present and excited. In the absence of disturbing factors such as self absorption and background or residual interferences, this function is generally considered to be linear. If the function is linear, and with zero concentration yielding zero intensity, the plot of log concentration against log intensity must be a straight line with a slope of unity. We will now discuss some purely mathematical considerations which develop the relationship between certain calculation curves and show that the prevailing practice of using a single emulsion characteristic curve over a wide range of wavelength will seldom result in a working curve with a slope of unity although this departure from unity may not affect the accuracy of such determinations.

Linearization of Characteristic Curves in Photographic Photometry

Gerard de Vaucouleurs
Appl. Opt. 7(8) 1513-1518 (1968)

The Effect of Light-Absorption on the Shape of the Photographic H. and D. Curve*

J. H. Webb
J. Opt. Soc. Am. 38(1) 27-34 (1948)

A Graphic Calculator for Spectrochemical Analyses

A. P. Vanselow and George F. Liebig
J. Opt. Soc. Am. 34(4) 219-221 (1944)

Three-Line Method of Obtaining Characteristic Curves for Heterochromous Photometry

Milton Green
J. Opt. Soc. Am. 40(12) 842-844 (1950)

Some Horticultural Applications of Spectrochemical Analysis*

B. C. Brunstetter and A. T. Myers
J. Opt. Soc. Am. 31(2) 163-166 (1941)