CCTV Reference Guide


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Security Recorders Digital (DVR) Time Lapse Event CCTV Cameras Indoor Outdoor Covert Waterproof Housings Accessories Color / BW Monitors Quad Single Channel Multiplexers 16 Camera Triplex Color Quad Splitter Retail Partners Professional Partners	The Security Labs customer support staff welcomes your call regarding specifications, operation, or the installation of any of our products. We can talk to you about your general requirements and answer questions regarding integration of any current equipment you may have. If you are new to video surveillance, we are eager to explain the benefits of CCTV and explore your questions. Customer Support 1-800-774-0284
	Suveillance/CCTV Glossary
	CCD: Charge Coupled Device. The chip that detects photons of light inside a CCD camera and converts them into an electrical signal. This signal is processed so it may be viewed or recorded. Best image quality. CMOS: Complementary Metal Oxide Semiconductor. Similar to a CCD, it also detects light for conversion into a signal. Lesser image clarity than a CCD, but more compact in size with lower power usage. COMPOSITE VIDEO: The signal that can be found on the video out jack of a TV, VCR, or camcorder. It is the combination of the RED, BLUE, GREEN (chroma), LUMINANCE (brightness) and video synchronization signals. FOV: Field of View. The horizontal and vertical height of an image from the camera. The FOV is calculated based on, camera imager size, subject distance, and focal length of the lens. IR: Infrared. A portion of the light spectrum higher in wavelength than the human eye can see. IR EMITTER: An Infrared light emitting diode (LED). LUX: A camera’s light gathering ability. The lower the number, the better the image in low light conditions. PIR: Passive Infrared. Widely used in devices to detect motion. A special lens on the front of the PIR divides the sensor into zones. A individual’s body heat radiation is detected as it moves through the sensor zones in front of the PIR. DVR: Digital Video Recorder. A device that records digital video images to a hard drive (HD) or other digital storage media.
	Why choose a digital recorder? During the last decade, microprocessor based (digital) technology has made major advances. Processors, hard drives, and computer memory are continuing to increase in speed and ability. In the surveillance industry, these advances have made it possible for recording digital video. A Digital Video Recorder (DVR) retrieves the video from a security camera, multiplexer, or other source, and converts the signal from analog to digital. The digitized video data is then compressed and stored on the DVR’s hard drive. Video compression (making the data size smaller) allows the digitized video to be stored efficiently. The process of storing the video data on the DVR hard drive is similar to the way your desk top computer stores a word processor or other data file. The file (video image) is ‘marked’ when stored so the user has quick access to it at a later time. Because the DVR operates like a computer, retrieval of data (video) is very fast. A search by event, time and date, or by camera, happens almost instantaneously. The resolution (image size) and quality (amount of compression) are features that can be set by the user and determine how large and how detailed the playback image is on the monitor. Setting the image for full screen playback with optimum detail requires the most data space on the hard drive and will lower the number of hours of video that can be stored before the hard drive is full. An “overwrite when full” feature assures the user that should the hard drive become full, the DVR will continue to record by writing over the oldest video first. Like time lapse recorders, DVRs can be set to record at different frame rates. The fastest any DVR or time lapse can record is 60 fields (images) per second. Setting the recorder to a much slower setting, for example, one image every 8 seconds, will greatly extend the total recording time. Like time lapse recorders, DVRs can also be set to event record when triggered by an external trigger such as a door contact, or by a preprogrammed schedule. Adjusting the DVR for the appropriate frame rate, image size, and compression is simplified with on screen menus. Advanced features (some models) allow you to connect to the DVR though the TCP/IP protocol in your desktop or laptop computer. The DVR can be connected to your office’s local area network (LAN) and cameras can be viewed at your PC monitor. If your LAN is connected to a broadband internet connection (DSL or cable), the DVR connected to the LAN can be viewed from home via the internet.
	How does IR work? The human eye can see in the visible light portion of the spectrum chart (below). Above visible light is infrared (IR). The CCD or CMOS device inside your security camera can detect IR light and use it to help illuminate the area viewed. Many Security Labs cameras emit IR so that the area in front of the camera can be seen in total darkness. ONLY black and white (B/W) cameras are affected by IR illumination. Color cameras will detect IR to a much lesser degree. Take your TV remote and press a button while pointing it at your camera for a simple demonstration of how a CCTV camera can see IR.
	How much will the security camera see? The field of view (FOV) is based on the camera & lens. Security Labs cameras are supplied with a wide angle view lens. Wide angle lenses are suitable for most applications due to their ability to view a large area. A 4mm wide angle lens will be able to view an area 20’ high x 26’ wide at 21’ away. As an example, a 15’ x 15’ room is shown in the diagram below. Observe that the 4mm lens (green arrows) allows better wide angle viewing coverage than the 12mm lens (red arrows). In applications where a closer view is needed (such as above a cash register or over a greater distance), an 8 or 12mm may be desired. The same camera (above) at 21’ away with a 8mm lens will have a 10’ vertical x 13’ horizontal FOV. At 21’ with a 12mm lens, the FOV will be approx 6’ vertical x 9’ horizontal. Increasing the focal length of the lens decreases the perceived distance to the viewing area. The SLC-110, SLC115, SLC-120, and SLC-1041 cameras have interchangeable lenses available in 8 and 12mm. See the FOV diagram below for approximate views with different focal length lenses.
	Can I use my VCR as a security recorder? If you are considering a recorder to document or review events around your business or residence, consider the important features found in a security recorder. A normal consumer VCR will work with any of our cameras and will record the image. Some features not found on a standard VCR and are available with Security Labs Time Lapse Recorders:
	Time and date stamp to know when an event occurred Extended recording (up to 40 days), instead of 8 hours Alarm, panic, and event recording when motion is detected No need to review hours of tape to find an event Automatic rewind and record, series recording Programmable inputs/outputs> Commercial motors for extended use High resolution (350 lines vs 230 lines on a standard VCR) Alarm scanning to quickly review events> Alarm counter, power loss logging, on screen titling
	How does a time lapse recorder work? A Security Labs time lapse recorder is set up in a very similar fashion to your home VCR. It is very simple to connect and operate! Time lapse recorders, as their name implies, slow down the recording process and create a time lapse between recorded frames The purpose behind having lapses between recording intervals is to increase the amount of recording time on an individual tape. Unlike a standard VCR which has a maximum record time of 8 hours, time lapse recorders (such as the Security Labs SL820) can record from 2 to 960 hours (1280H w/ a T160 tape) on one standard VHS tape. With a time lapse recorder, one can be assured that his or her property has active surveillance recording around the clock. The playback of a Security Labs time lapse will always have a clear, noise free, high resolution picture. The table below demonstrates the increased time between images in extended record speeds. Note that in the 2 hour recording speed the interval between images is 1/60 second. This is the same recording interval that a consumer VCR has and will playback the video in full motion real time (no time delay). In the 960 hour recording speed, a 8 second lapse will occur between images. Audio (sound recording) is not available in speeds slower than 18 hours. Analog time lapse recorders do not offer many of the features that DVRs do, but provide extended security recording at an affordable price.
		RECORD SPEED 2 Hour 6Hour 18 Hour 24 Hour 36 Hour 48 Hour 72 Hour 96 Hour 120 Hour 168 Hour 240 Hour 360 Hour 480 Hour 720 Hour 960 Hour	INTERVAL 1/60 second 1/60 1/20 .22 .32 .42 .62 .82 1.02 1.42 2.02 3.02 4.02 6.02 8.02	AUDIO Yes Yes Yes No No No No No No No No No No No No