Veiling Glare (Flare)

DEFINITION:

The phenomenon in which light spreads over the film plane due to dispersion from optical elements or light reflections inside the camera or lens.

DESCRIPTION:

In addition to the normal image-forming light, light reflected from the lens, diaphragm blades, and body interior. Spreads on the image plane without forming an image.

This occurrence is called veiling glare or flare. When caused by aberration they are called halations, and those which form images with reflections are called ghosts. It is difficult to identify these on a photograph.

Light which reaches the film plane without contributing to the image formation of an optical system is generally called flare, and it is better to consider ghosting as a type of flare.