Halogen:
Any of the four non-metallic elements fluorine, chlorine, bromine and iodine.
Related info: Types of lighting
Head (1):
The component which records an electrical signal onto magnetic tape, or reads a signal from tape into an electrical signal.
Related info: Cleaning video heads
Head (2):
The part which the camera is mounted on, atop a tripod, pedestal or other mounting. Allows the camera to pan and tilt.
More info: Camera tripods
Headroom:
The amount of space between the top of the subject's head and the top of the picture frame.
More info: Camera framing
HDBaseT:
A digital connection used in home entertainment systems, designed to carry video, audio, ethernet, power and control data over a standard Cat5e/6 cable.
More info: HDBaseT
HD DVD:
A high-definition DVD format supported by a group of manufacturers led by Toshiba.
More info: The HD DVD Format, HD-DVD vs Blu-ray
HDCP:
High-bandwidth Digital Content Protection (AKA High-Definition Copyright Protection). A method of copy protection that prevents audio and video signals being copied across digital connections.
HDMI:
High-Definition Multimedia Interface. A digital connection used in home entertainment systems.
More info: HDMI connectors, HDMI cables
HMI:
Hydrargyrum Medium-Arc Iodide, a type of light which uses an arc lamp instead of an incandescent bulb to produce light.
More info: HMI Lights
Hot (1):
An image or part of an image which is excessively bright, i.e. overexposed.
More info: Iris & Exposure
Hot (2):
The wire in a cable, and the connecting pins, which carry the signal.
Related info: Audio cables and connectors
Hyperfocal distance:
In cinematography, the distance from the camera beyond which all objects can be brought into acceptable focus.
Related info: Focus
Hz:
Hertz. Cycles per second.