Differences in Radiance: relative effects of temperature changes and emissivity changes.

Calculations are made for the relative effects of temperature change and emissivity change causing a change in radiance. These are done for the total radiation and the monochromatic radiation at the wavelength that maximizes the contrast. They are done for no background contribution, a uniform background, and a general, nonuniform background. The general result, subject to some of the details, is that for a 300 K ambient, changes in emissivity of 0.01 correspond to a temperature change of about 0.5 K.