A Guide To Selecting The Correct Video Surveillance System To Meet Your Needs
Don't Buy A Surveillance Camera Kit Until You Read This
Educate yourself before you buy a security camera, digital video recorder or a complete security camera system. With thousands of security cameras and related products from hundreds of manufactures such as Pelco, American Dynamics, Honeywell, Sony, EZWatch Pro and Armor-Pro Video Surveillance Systems, it can be difficult and daunting task to sort through all of the features and benefits to find the surveillance system that best meets your needs.
Take advantage of our experience which has been developed from 20 years of designing and installing high end, state of the art digital video surveillance systems. Don't be confused by the many ads and offers out there designed to mislead you, know exactly which features and benefits you need before you pay for something you don't need or get stuck with a digital video recorder that doesn't quite meets your needs.
The Heart of Every Security Camera System Is the Digital Video Recorder
There are three major categories of digital video recorders or DVR's as they are sometimes referred. There are the hardware based digital recorders, PC based digital video recorders and the newer IP based digital video recorders. No more VCR tapes are required as all of the surveillance video is recorded onto internal hard drives. How long the video can be stored is merely a function of the total images per second being recorded, the size of the image files and the total size of the installed hard drive(s).
Hardware Based Digital Video Recorders
Operating much like a VCR, complete with shuttle and jog controls, most stand alone digital recorders will utilize some type of traditional CCTV or SVGA Video monitor to view the video. Stand alone, hardware based DVR units are built from the ground up to perform one specific function, record security camera video. With the video capture cards providing the video compression and only basic Linux operating software, these hardware based DVR's are extremely stable and easy to use. Many of these systems can record real time high resolution video from 16 or more cameras using H.264 or MPEG-4 compression.
PC Based DVR's
PC Based digital recorders are comprised of a computer, video capture cards and a software package that allows full motion security camera video to be recorded and played back on a standard personal computer. Many PC based digital video recording systems are capable of recording up to 480 images per second, which equates to 30 images per second, or real time video for every security camera connected to the system. PC based DVR's use video compression such as MPEG-4 or H.264 to compress the recorded images into manageable file sizes for archiving on the hard drives. This video compression allows a huge amount of surveillance video to be stored on the DVR's hard drive. On average, a four camera digital video recorder will archive about 30 days of surveillance video on one single 80 gig hard drive. To double the recording days simply add another 80 gig hard drive. Some people consider the PC based Digital Video Recorders to be easier to use and more flexible than the Digital Hard Drive Recorders, and they offer selectable recording resolution that are up to 4 times greater than the resolution of the old Time Lapse Recorders. You can choose to record images from your security camera at resolutions of 720x480 or greater.
PC based DVR's are designed so they do not require any scheduled actions or maintenance to provide uninterrupted video recordings. Recorded security video is played back on the computer monitor and it can be printed, saved to a floppy disk or burned to a CD. Most PC based digital recording systems allow you to view and playback any combination of CCTV cameras without interrupting the video recording process. A very popular feature of the PC Based Digital Video Recorders is that they support remote viewing of your security camera system from any PC that is properly equipped. Most PC based digital recorders are provided with remote viewing software packages that allow you to check your security cameras from your home or office at any time from a remote location via the internet.
IP based digital video recorders or network security recorders (NDVR)
Web based video recorders offer many advantages over both stand alone and PC based digital recorders. Network security recorders can be used in either a stand-alone system or a client/server configuration, providing flexibility from small to large scale operations. Network security recorders utilize your wide area network or the internet to transmit video signals from the cameras to the video recorders; therefore security video recording becomes non-centralized. Now, you can view and record security camera video from all over the world in one location, or from several locations simultaneously. This makes security IP video monitoring systems perfect for a broad range of security applications including banks, retail outlets, transportation centers, offices and more. In addition to sophisticated monitoring functions, network surveillance recorders can support a large number and wide variety of IP addressable security cameras from different manufacturers, and many support standard analog CCTV security cameras as well. The hybrid functionally of IP digital video recorders provide a migration path for users of analog CCTV systems to upgrade to the latest generation of digital security cameras.
Which Digital Video Recorder Is Right For You? The final choice might come down to budget or custom features that you can't live without. Whether you choose a super stable stand alone DVR or decide on a a state of the art PC Based Digital Video Recorder, you are sure to improve the safety and security of your home or office by installing a Video Surveillance System.
Choose the Right Security Cameras
If the Digital Video Recorder is the heart of the security camera system, then the security cameras are the eyes and ears that can offer you a piece of mind that is hard to match with any other type of electronic security equipment. Security cameras never lie and the forensic evidence provided from CCTV video has been used to convict thousands of criminals. Security cameras can protect you from risk. Closed circuit television cameras are a great tool for crime prevention because they discourage your customers and employees from stealing and they can greatly reduce your exposure to litigation. The quality of the security cameras that are included in your kit will have a major impact on the total overall usefulness of your surveillance camera system.
Color or Black & White
The price difference between color and black & white security cameras used to have a significant impact on your purchasing decision. Today, the cost difference between a color and black & white security camera is very minimal, but there are other performance considerations that need to be calculated into your purchasing decision.
Black & white security cameras normally provide a higher resolution image that can provide finer details and a crisper picture from any given scene. In addition, B&W security cameras tend to have much better low light capabilities than traditional color surveillance cameras.
That being said, most people still prefer the vivid clarity and depth that color CCTV cameras can provide even though a standard color security camera still requires about 4 times the light of a black & white camera to provide usable images. Of course there is the obvious benefit of being able to tell the police that the perpetrator had on a green shirt and was driving a yellow Mazda.
Which do you choose, vivid color or low light recording? Many manufacturers have addressed this very question by creating security cameras with infrared night vision capabilities built right into the camera.
There are several types of night vision cameras with the most common and inexpensive simply adding Light Emitting Diodes (LED's) to the camera to provide night vision. The more expensive day night security cameras utilize dual CCD imagers. One imager provides high resolution color images during the day and while the other imager is used to provide high sensitivity low light black & white images at night. The top of the line night vision cameras utilize low light intensifiers or forward looking infrared to see in total darkness. These top of the line infrared night vision cameras are extremely expensive and normally used in very high security applications.
Analog or IP Based Security Cameras
Traditional security cameras utilize CCD digital imagers to produce a digital video signal which is converted to an analog signal so that it can be transmitted via a wire back to a centralized viewing or recording system. At the head end, the analog signal is converted back to digital for viewing and storage.
Conventional Analog CCTV systems require a home run cable between the camera and the recording or viewing device. The most common transmission method is RG-59 coaxial cable, but telephone cable and fiber optic cable can be used as well.
As computer networks and structured cabling systems gain the ability to carry more data, Web based and IP security cameras will become more and more common. Internet based security cameras provide the ability to plug into a network port and then be viewed or recorded from anywhere in the world.
IP based video security systems offer many benefits such as faster installation, remote viewing, decentralization of monitoring centers and the ability to share video and view and record it in multiple locations. IP based security cameras are still relatively expensive, but as the technology expands and becomes more common, the prices will eventually fall and come more in line with traditional CCTV cameras.
Depending on your level of expertise, the application and the extent of your existing network infrastructure, web based security cameras can provide a cost effective alternative to traditional coaxial based security camera systems.
Fixed Position Cameras or Pan Tilt Zoom Security Cameras
A fixed position security cameras field of view is limited by several factors including placement and lens selection. Depending on the focal length of the lens, a standard security camera can provide a filed of view from about 90 degrees to 15 or less degrees in width. The wider the field of view, the closer an object or person needs to be for recognition. A security camera with a 2.8-mm wide angle lens would not provide usable recognition of a person standing much more than 10 to 15 feet away, but it would provide a wide angle view of an entire office. The same security camera with a 40-mm lens could provide recognition of a person standing 60 to 80 feet away, but it would not provide any coverage of an incident that happens 6 feet away and slightly to the left or right of the camera. Lens selection and camera placement are key to a successful deployment of a video surveillance system.
PTZ security cameras can cover large areas with their high resolution long range auto-focus lenses. Many PTZ security cameras offer 22x optical zoom lenses with 12x digital zoom that effectively provide a 264x zoom. These high speed pan tilt zoom cameras can read license plates from thousands of feet away. True day night PTZ dome cameras operate in extremely low light conditions by switching from color to black & white and they offer additional features including 360 degree rotation at over 250 degrees per second, window and zone blanking and on screen displays. Modern PTZ Security cameras can run pre-programmed patterns that cover thousands of square feet.
PTZ security cameras can cover large areas, but they can be expensive compared to fixed position surveillance cameras. You could purchase and install 4 to 6 fixed position security cameras for the price of one pan tilt zoom. Could you get the same or better coverage from 6 fixed cameras or 1 PTZ? That is for you to decide, but remember that if you are looking at a license plate 1000 feet away from a PTZ camera, you might be missing incidents that are occurring right by the camera or on the other side of the parking lot.
Network Mega-Pixel IP Security Cameras
Web based mega-pixel security cameras are revolutionizing the security industry by offering security cameras with up to 20 megapixel video imagers. These new mega-pixel security surveillance cameras can view and record very large areas with wide angle super high resolution imagers. A single mega-pixel security camera can cover and record the same area as 6 or more traditional CCTV security cameras and still provide you with the ability to pan tilt and zoom into areas of interest, while still recording the entire wide angle view. These cameras are still considered cutting edge and they are very expensive, but in certain applications, they can provide a very cost effective and efficient alternative to traditional CCTV video cameras.