Focal Length

Technology / Television (TV) / Focal Length: The distance from the lens' optical center to its focal point, usually measured in millimeters. There are three conventional types of focal length: wide angle, normal, and telephoto.

Other Words for Focal

Focal Noun Synonyms: central, focused, concentrated, convergent, centred, centralized

Other Words for Length

Length Verb Synonyms: extent, measure, span, reach, size, magnitude, dimension, measurement

Equivalent Focal Length

Entertainment / Photography / Equivalent Focal Length: Distance in a lens between the front nodal point and the focal plane when the lens is set to focus a subject at infinity. In a telephoto lens the equivalent focal length is shorter than the back focus MORE

Afocal Lens

Entertainment / Photography / Afocal Lens: Lens attachment that alters the focal length of the camera lens without disturbing the distance between the lens and the film plane. MORE

Fixed Focal Length

Entertainment / Photography / Fixed Focal Length: Camera system whose lens cannot be interchanged for a lens of different focal length. MORE

Zoom Lens (Variable Focal Length)

Technology / Television (TV) / Zoom Lens (Variable Focal Length): A lens with a variable focal length, allowing the operator to shift immediately and continuously from wide angle to telephoto (or vice versa) without switching lenses. MORE

Focal Plane Shutter

Entertainment / Photography / Focal Plane Shutter: Shutter which lies just in front of the focal plane. Light sensitive film positioned at the focal plane is progressively exposed as the shutter blinds move across it. MORE

Focal Point

Science / Astrology / Focal Point: Any point in a horoscope where several influences converge or disperse, such as the position of the squared planet in a T-square formation, the action point in a yod, the handle of a bucket, etc. See MORE