Aspect Ratio
The ratio of the picture frame width to the picture frame height in standard TV systems.
Auto Focus
The lens continuously adjusts to the correct focus automatically for the sharpest picture.
Auto Iris
Security cameras with auto iris, have the ability to compensate for large variations in light levels. This is useful for security cameras that need to adjust for changes from bright sunlight to darkness or night.
Auto White Balance
The ability of a color camera to automatically balance flushes of white light into the aperture.
Automatic Gain Control
A function on the camera that automatically balances the gain, or volume, of the signal, and raises the volume if it is too low and lower it if too high.
CAT5
(Category 5) A twisted pair cable that is capable of transmitting data at high speeds (100 megabits per second and faster). CAT5 cable is commonly used for voice and data applications.
CCTV
Closed-circuit television.
Day/Night Camera
A camera that is ‘Day/Night’ means it can capture video in both day and nighttime.
Fixed Lens
A camera lens where the camera’s focal length is permanently set and cannot be adjusted by the user.
Focal Length
The distance from the optical center of the lens to the image of an object located at an infinite distance from the lens. Long focal lengths give a small field of view (e.g. telephoto effect), while short focal lengths give a wide angle view.
Frames Per Second (FPS)
In digital video applications, refers to the number of video images that can be captured, displayed, or recorded in a second.
H.264
Currently, the most advanced form of compression. It saves space on your HDD while preserving image quality.
Infrared
Frequency range within the spectrum of light that is invisible to the human eye.
IP Camera
A CCTV Camera that can transmit video and audio over TCP/IP network. An IP Camera can connect to a local network and streams it’s video over the network to a Network Video Recorder.
IR Cut Filter
An IR Cut Filter is an extra filter inside the camera that moves behind the camera lens when it gets dark. A camera with an IR Cut Filter will produce very high quality images in low light conditions.
ONVIF
ONVIF is an open industry forum for the development of a global standard for the interface of IP-based physical security products. Creates a standard for how IP products within video surveillance and other physical security areas can communicate with each other
PIR (Passive Infrared) Motion Sensor
A PIR Motion Sensor detects motion by looking for changes in temperature at any given point in its field of view. If a person walks in the PIR motion sensor’s field of view, the PIR motion sensor will detect the movement of the person’s body heat.
PTZ
Pan Tilt Zoom. A camera that can be controlled via Joystick or DVR and moved up/down, left/right and zoomed in/out.
Real Time
Images are normally recorded at 50 individual frames (pictures) per sec. When played back at this rate, the human eye sees the images as continuous movement.
RG59
A type of CCTV Coaxial cable used to transmit cctv camera video signals to a CCTV System.
Varifocal Lens
A cctv camera lens whose focal length / viewing angle can be manually adjusted to suit the camera view required. Typical Vari Focal lens lengths are: 2.5mm-10mm, 3.5mm-8mm, 5mm-50mm