Telephoto = In order to make distant objects appear larger, cameras require a telephoto lens.…

SDTV = Standard definition television…

Resolution= Refers to how much detail can be captured on a camera or displayed on a monitor. Cameras typically capture about 380 horizontal lines of resolution. High resolution analog cameras may capture 450 lines of resolution or more. High resolution IP cameras can record and stream in HD/Megapixel quality. The higher the resolution, the more detail that can be captured in a picture. The monitors and recording devices can generally handle at least as much resolution as the cameras can capture. Also remember that higher resolution images capture larger size frames (file size), and therefor, require more bandwidth to transport and more storage space to archive.…

Remote Surveillance= The ability to view cameras from an alternative location. Many current DVRs have an on-board Ethernet (RJ45) part, which allow them to be “networkable,” and allow them to be viewed remotely over a WAN. All NVR systems accommodate remote surveillance.…

PTZ = Pan, Tilt and Zoom. PTZ cameras have the ability to be “remotely controlled” allowing a user to take control of the camera and manipulate it using a joystick or embedded software PTZ controls in NVR or DVR software. The Axis 213 is an example of a PTZ camera. Currently, most PTZ cameras do not support Power over Ethernet because of their specific power requirements.…

Progressive Scan = The process whereby a picture is created by scanning all of the lines of a frame in one pass. Many analog surveillance cameras use Interlaced Scan as opposed to Progressive Scan, and are not good at capturing moving objects with clarity. Most IP cameras use Progressive Scan, making them superior for tracking and capturing moving objects, such as a license plate on a vehicle.…

Patrol = Cameras that have the ability to PAN can often also support a “Patrol” sequence. Often, cameras set to patrol simply pan left to right in a predetermined motion, allowing the camera to view a larger area.…

PAL = Television format for most of Europe and South America.…

Optical Zoom= Changing the focal length of a camera by adjusting the physical zoom lens.  The higher the optical zoom, the better the results.  In a camera, an optical zoom of 10x or more is called a “superzoom” lens.  Note that if a camera is advertised with “10x zoom,” that does not necessarily mean optical zoom only.  In many cases, the optical is 3x with the additional 7x being digital.…