Jacks: Bracing frames attached to the back of scenic elements to keep them from falling over.
Keystone Error: An incorrect shape in a projected image when the projector is not located correctly in relation to the screen.
Lamp: Proper term for a light bulb. In show business also refers to the entire luminaire fixture.
Lumen (lm): A measure of the perceived power of light to the human eye.
Luminance: A measure of the brightness of a video display or signal.
NTSC (National Television System Committee): The video standard protocol in the U.S.
PAR Can: A common, basic stage lighting fixture that houses a PAR lamp.
Pin Spot: A very narrow beam lighting fixture.
Pipe & Base: Lighting stands using cast iron bases and threaded steel pipe for the upright.
Pipe & Drape: Aluminum pipe uprights and adjustable horizontal crossbars that hold up draperies and curtains at trade shows and events.
Pixel (short for Picture Element): The smallest addressable element used to build an image.
Pre-Rigged Truss: Truss sections that contain lighting fixtures and cabling for easy set up at an event.
Projector Throw Distance: The length from the lens of a projector to the screen necessary for a particular unit to produce an image of a specified size.
RGBHV (a.k.a. 5 Wire): A five-component analog video format that separates red, green, blue information and horizontal and vertical sync into five signals.
RGsB (a.k.a. Sync On Green): A three-component analog video signal comprised of a red channel, blue channel and a green channel with composite sync.
S-Video (a.k.a. Separated Video or Y/C): An analog format that separates brightness information (luminance or Y) from color information (chrominance or C) in a video signal.
Scaler: Stand-alone unit or a feature in a display device that changes the size of an image.
Scan Conversion: The process of changing the horizontal scan rate of one device to that of another.
Soft Patch: A system allowing control and diming/fixture channels to be assigned without following a set format.
Special: A stage light used to highlight a performer or scenic element.
Sync (Synchronization): Timing information to insure images display properly.
Universe: A group of 512 DMX channels.
Zip Strip: Originally a fixture from Altman and now a common name for any compact strip light that uses small MR16 sized bulbs.
Craig Leerman is senior contributing editor of ProSoundWeb and Live Sound International, and is the owner of Tech Works, a full-service production company in Las Vegas.