achromatic

A color without hue: white, any shade of gray, or black.

active space

The space in front of a moving subject that he/she/it appears to be traveling toward.

aliasing

A jagged, stair-step effect on curved or diagonal lines due to the limits of resolution of a digital image.

alignment

(Gestalt) Lining up elements along their edges or centers, following a vertical or horizontal axis, to create a sense of order and purpose.

ambient light

Indirect illumination caused by light bouncing off surfaces near the subject.

armature

The fundamental lines of direction of flow that connect the main compositional movement to the picture plane. See diagonal armature, harmonic armature, rule of thirds.

audition

An interview with a photographer, casting director, etc., to evaluate the model’s suitability for a specific job. At an audition you may be asked to show a portfolio or dress in a certain style.

background

Parts of an image that are behind the main subject and not considered additional subject. Also see ground and negative space.