Exposure

The quantity of light allowed to act on a photographic material; a product of the intensity (controlled by the lens opening) and the duration (controlled by the shutter speed or enlarging time) of light striking the film or paper.

Kodak – Glossary of Photographic Terms

Blur

Image unsharpness, such as that caused by inaccurate focusing or movement of the subject or camera during exposure.

L. Stroebel

Bleed

A term used by photographers and graphic artists to define an image that runs to the edge of the picture or page without any borders.

R. Welsh

Rotoscope

Trade name for an animation production device, originally developed and patented by Max Fleischer studios in 1917, that is used to project live-action images, one frame at a time, onto a screen, where they can then be traced by an animator, facilitating the reproduction of complicated movements, the making of traveling mattes, or the creation of a realistic cartoon style.  A common term for any system or technique of using live-action footage as a guide in animation.

H. Lester

Retina

The internal lining on the back of the eye that contains light sensitive rod and cone receptors and a network of nerve cells.

L. Stroebel and R. Zakia

Original

The term original refers to the negative (positive if reversal processed) or image file from a digital camera that was in camera when the object was photographed.  It also applies to sound recordings on film, or video recordings.  Original are also materials from which copies are made, such as handwritten, typed or computer generated documents, printed material, tracings, drawings, etc.  The term can also apply to original work/s of art.

I. Current (Updated by R. M. Elliott)

Diffuser

Any light-scattering medium placed in the path of a beam of light so as to soften the character of the light.

S. Ray

See also: Diffusion