Definitions for "Halation"
An appearance as of a halo of light, surrounding the edges of dark objects in a photographic picture.
A spreading or reflection of light, a halolike effect that occurs in reverse reading letters, where the background is significantly darker than the illuminated letters.
A term originally used in photography to denote the process by which the image in a developed emulsion is spread beyond the bounds of the incident light. Is used to describe the spreading of light from one order to the next in an ├ęchelle spectrogram.
An effect caused by extreme contrast between the illuminated and unilluminated portions of a sign and which affects the ability of the eye to focus on that sign. The effect is also dependent on color.