CCTV Glossary A to E

Aperture

Aperture is the area of the camera lens that gathers light. The Iris
of the cctv lens controls the size of aperture.

Auto Iris

Auto Iris Lenses adjust for changing light conditions in a camera view.
If the sun shines on a camera with an auto iris lens, the lens will adjust
the amount of light so the picture remains clear.

CCD

Charge Coupled Device - a light sensitive imaging device for almost all
cameras. Typical sizes for CCTV cameras - 1/2", 1/3", 1/4".

C Mount

Type of screw-on mounting for CCTV Camera Lenses. C Mount lenses need
an adapter ring when used with CS Mount camera (see CS Mount).

Compression

Compression Techniques are used in Digital CCTV to reduce the file sizes
of recorded video images. Typical compression formats used for video are:
MJPEG, MPEG-4 & H.264.

CS Mount

More recent type of mounting for CCTV Camera Lenses. Designed for 1/2",
1/3" 1/4" CCD cameras, CS-Mount is the more common lens mount
used today in CCTV cameras.

Day/Night Camera

A camera that is 'Day/Night' means it can capture video in both day and
nighttime.

In low light conditions, the Sony Day/Night chipset switches from colour
to black & white at night to enhance the picture quality

DSP

Digital Signal Processing - a technique by which video quality can be
improved by adjusting parameters of the video signal.

DVR

Digital Video Recorder - CCTV Footage is converted to a digital signal
and stored on a PC Hard Disk. This is now the standard CCTV recording
practice.

ExView

Sony Chipset type that offers very good images in both day and night
time. Typically, cameras with Ex-View chipset have good Low Light (LUX)