Wednesday, July 13, 2011

CCTV Video Monitor

 
The Closed Circuit TeleVision or CCTV Video Monitor is one of the most vital components of a CCTV digital video security system.  Interestingly however, today’s systems can actually run without one.  What’s more, the technology for monitors is constantly improving which means that at today’s changing technological improvements, a monitor bought today could be obsolete a year from now.  Read on to find out some more interesting facts about the CCTV video monitor.
Based on how a CCTV video monitor is used we can categorize them into three major groups.  The first is the installation or set-up monitor.  This monitor is often only 2 to 6 inches big and is used when the system is first installed and needs to be set up.  Generally, digital video cameras may be mounted far away from the Digital Video Recorder or DVR unit and the system monitor.
Using this monitor eliminates the need to run back and forth to the DVR to aim cameras, and run general setup and diagnostics procedures.  This type of monitor is incredibly handy–especially if you have a 32 camera system and each camera needs to be adjusted.  After setup is complete, this monitor is removed from the system.  IPTEC sells a 2.5 inch LCD setup monitor that includes a wrist strap.  For more information, see our product number#VX-WLCDM.
Another type of CCTV video monitor is known as a “spot monitor.”  Sometimes it may be necessary to constantly monitor a specific camera in a multi-channel system.  For example, a retail store may have an 8 camera system, with one camera aimed specifically at the cash register area.
A spot monitor is connected to this cash register camera but can be located away from the area that all the other cameras terminate (usually the DVR).  Using this method for example, a store manager could have the spot monitor placed in his/her office located far away from the camera and/or DVR.
If the spot monitor is used on a “non-wireless” or “cabled” system, an additional cable must be run to the spot monitor in addition to the DVR.  This is usually accomplished by adding a splitter to the cable at some point to create one feed to the spot monitor and another to the DVR input.
The third type of security camera monitor is the system or main monitor.  This monitor is generally connected to the DVR by one or more cables and displays the on-screen information of all the system cameras and the DVR.  Usually this monitor is bigger in size than a spot monitor so that it can accommodate the simultaneous displaying of all or groups of cameras in the system at the same time.
CCTV video monitors are like televisions (or perhaps more like personal computer monitors) in composition.  There are basically two types of monitors that are used today, but generally there is only one type that is used the most often.  The two types based on composition are the CRT and LCD (and now LCD/LED) monitors.
The CRT or Cathode Ray Tube monitor is the oldest type.  As its name implies it works by shooting a beam of electrons in a horizontal fashion on the back of the monitor’s screen.  The CRT monitor is bulkier, heavier, and generally produces a lower resolution picture than the LCD monitor; basically, its equivalent to the older models of televisions that also used a CRT.  These monitors are still used today, but are being edged out of the market by lighter more efficient and less bulky LCD monitors.
The LCD or Liquid Crystal Display security camera monitor is probably the single most popular monitor type in use today.  It is much lighter than the CRT, it uses less energy, and displays at a much higher resolution and color, capable of providing quality high definition displays.  These monitors were once limited in size, but as technology advances so do the available sizes.  IPTEC offers monitors as large as 42 inches.
One last note; if you are considering purchasing a CCTV video monitor, regardless of the type, make sure the monitor has the proper connection input type available.  Our DVRs have HDMI, VGA, and BNC connections to make connecting the monitor an easy process for you.  However, many monitors, especially those once used for computers, only have a VGA connection for example.  So be certain to make sure your monitors, camera and DVR display types, and connectors match.
Source : http:// www. security cameraking .com/ securityinfo /

Surveillance CCTV Software

 Surveillance CCTV software is the intermediary that ties together digital video cameras and Personal Computers (PCs) or Macintosh Computers (Macs) as well as Digital Video Recorder (DVR) units for standalone systems.  It’s also the main portion of remote DVR monitoring applications (Apps) that allows your smartphone to access your video security system.  It essence it provides the programming that allows you to control the camera, monitor the camera, and record the digital video files.

There are many types of surveillance CCTV software.  Perhaps the simplest to use is a typical web browser such as Internet Explorer, Firefox Mozilla, Google Chrome and others.  For digital video security cameras and DVRs that are IP (Internet Protocol) ready, a web browser may be all that is needed to control, monitor, and record digital video security images.

Although it may be difficult to describe what surveillance CCTV software is, we can easily describe what it isn’t.  Surveillance CCTV software is not firmware.  Firmware is basically the drivers and internal commands that a device needs to communicate with processors and other devices.  Firmware is device and manufacturer specific.

Surveillance CCTV software is not Operating System (OS) software.  Operating systems like Windows, Linux, Mac, and others provide the basis for central communication between devices, processors, and users.  OS software is what makes a computer system work.

So where does that leave us with surveillance CCTV software?  As stated earlier it could be considered as a web browser, but typically surveillance CCTV software is specific programming that is designed to operate a digital video security system.  We can list the types of surveillance CCTV software based on how they are designed to work.  Surveillance CCTV software can be:

* Designed to provide the control, monitoring and recording of security cameras and DVRs;

* Designed to allow PCs and Macs to provide the control, monitoring, and recording of security cameras when used in conjunction with a security video PCI card;

* Designed to provide the control, monitoring and recording of security cameras and DVRs that may be networked using the Internet (IP ready);

* As mentioned earlier, designed as Apps for Smartphones to allow them to monitor IP ready cameras; and

* Designed to integrate a variety of digital video capture devices such as webcams, net cams (or IP ready cams), computer PCI capture cards and computers to create a digital video security system.

The first type on our list is software that is normally provided when you purchase a standalone digital video security system with a DVR.  The manufacturer of the DVR or the Cameras (or both) may provide the software that is normally installed on the DVR unit.  This software is used to control camera functions such as Pan-Tilt-Zoom (PTZ) functions and timers that turn the cameras on and off.

The second type of surveillance CCTV software on our list works with computers that use a PCI card.  There are some digital video security systems that are specifically designed to work with your computer.  For example Geovision brand PCI DVR cards provide inputs for multiple security cameras that connect to your computer.  This system uses your computer’s hard drive as the DVR.  The software that accompanies this card that allows the computer to control the cameras and store the digital video files is a type of surveillance CCTV software.

Our third type applies specifically to IP ready digital video cameras, DVRs and servers, and systems.  The software is normally produced by the manufacturer of the security system and is designed to allow a computer to control, monitor, and record security video using the network.  As mentioned at the beginning of this article, it may be something as simple as a web browser, but it can also be a proprietary program produced by the security equipment manufacturer that is used to coordinate the video security system’s functions.  These may also be in the form of browser plug-ins such as ActiveX subroutines that must be installed in the browser before it is used with the system.

The fourth type of surveillance CCTV software is Smartphone Apps which we have already described.

The fifth and final type of surveillance CCTV software allows you to use a variety of video capture devices (such as webcams or capture cards) in conjunction with your computer to create your own digital video system.  While this does not create the ideal video security system, it does save money by allowing you to use equipment you have already purchased to create a digital video system.

Surveillance Camera Lens

 

Surveillance camera lens are slowly beginning to evolve with the technology that supports them.  Before the digital age, a good majority of the surveillance cameras required that a lens be purchased for each camera.  Presently, some cameras still work that way, but the vast majority has the lens built right into the camera.  These lenses are often referred to as “board lenses.”
There are three major types of digital video camera based on their shape, the box type, the bullet type, and the dome type.  Basically the bullet and dome type cameras come with a lens already built into the unit.  This is often referred to as a board lens.  The box camera however, almost always requires the purchase of a lens.
As far as the lenses go, there are two different types of surveillance camera lenses, fixed and varifocal.  Fixed lenses do exactly what their name implies; they stay fixed in a certain immobile position.  Varifocal lenses have the ability to change their focal length either manually or remotely depending on the lens.
This means that for fixed lenses, the size of the field of view never changes; the lens can’t alter its own focal length so the width of the capture shot never changes.  This is great for use where there is no need to mess with changing the focal length regularly such as monitoring a parking lot, an entrance or exit, and other uses where zooming in on a subject or object is really not required and the camera will not be moved around a lot.
Varifocal lenses on the other hand, can move in and out changing the size of their focal length.  This is particularly handy when it is necessary to change the camera’s field of view to accommodate moving objects, tight shots, etc.  The focal length of a varifocal surveillance camera lens is normally expressed in millimeters (mm).  For example a fixed camera lens with a focal length of 3.0 mm will produce a fairly wide angle shot, whereas a focal length of 15.5mm will produce a narrow angle shot.
The nice thing about a varifocal lens is, depending on how it is made, you can get a focal length as small as possible and any focal length in between its maximum focal length.  It’s important to note that some of these varifocal lenses must be moved manually (by hand) while some our connected to a motor that drives the lens and is controlled remotely.
As long as we are on the topic of surveillance camera lenses, we’ll also mention a few of the characteristics of lenses that you probably should be aware of in addition to just focal length.  Four other points come to mind:  1. Depth of field; 2. F stop; 3. CS or C mount; and 4. Manual or Auto Iris.
Depth of Field
The depth of field is the distance from the camera to the object at which remains in focus.   Generally, the higher the F stop and tighter the Iris positions, the more objects that will be in focus.  In other words, a large Depth of Field means almost all objects in the Field of View can be in focus.  On the other hand, a small Depth of Field will only allow a small section of the Field of View in focus.
F Stop
The F stop is the foacl length divided by the effective aperture diameter.  In much simpler terms, the F Stop is an indication of the speed of the lens.  Since light must pass through the lens to the sensor, the F Stop gives us an idea of how much light it will absorb during the process.  A low F Stop lens is very efficient whereas a high F stop lens will require a lot of light.
CS or C mount
There are two standard surveillance camera lens mounts the “CS” and the “C.”  The difference between the C and CS is found in the distance between the lens and the CCD (Charged Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor).  The C mount distance is 17.5mm while the CS mount is 12.5mm.

Iris
The iris works with the surveillance camera lens to control the amount of light entering the camera via the sensor.  For cameras mounted in positions that have changing light sources, it is a good idea to use a lens with an automatic iris.  For cameras used inside or in environments where the light conditions seldom ever change, manual irises are sufficient.
Source : http:// www. security cameraking .com/ securityinfo /

VGA Monitor Converter

 
  
 Do you need a VGA Monitor Converter?  It seems as though when computers have reached their point of obsolescence, apparently the monitor just keeps on going, and going, and going…well you get the point.  Also, with the relatively recent use of LCD monitors (which supposedly last longer than the older CRT monitors) it seems as though a small surplus of monitors is beginning to amass amongst John Q. Public.
 
So what do you so with an older monitor that is no longer being used for your computer?  Turn it into a digital video camera security system monitor, what else?  It seems as if these monitors make especially good spot monitors for viewing the field of vision of just one camera, although they could also be used as whole system monitors as well.
 
There is just one snag in this whole idea.  Computer monitors have also gone through their changes as a result of the ever changing computer industry.  Today if you buy an LCD TV or a computer monitor you’ll notice there are a ton of different hook-up options available, usually on the back of the TV.  However, the older more mature CRT monitor that you want to use for your security system normally has a VGA input cable connector but your DVR only has a BNC connector.
 
That’s when it’s time for a VGA Monitor converter.  In fact, IPTEC has just what the doctor ordered.  Product# BNC-VGA is a VGA monitor converter that provides a high quality video image even after conversion.  This premium quality converter can convert your BNC output into a VGA output so you can use just about any VGA monitor as a security monitor.
 
Some folks may have bought big screen TV’s or elaborate computer monitors in the past that are no longer be used by the household.   Instead of tossing them in the recycle bin if they still work, use them as a security monitor.   The VGA monitor converter will allow you to do that easily and quickly.  All you have to do is plug in your BNC connector to one end and your VGA cable into the other end, and that’s it.
 
IPTEC’s bundled system packages all have Digital Video Recorders or DVRs that have VGA outputs as well as BNC.  In fact, only the elite-Mini Economy series has just a VGA and BNC connection.  Higher level DVR’s in addition to BNC and VGA hookups, may also offer HDMI for high definition security coverage.
 
If you take a look at the monitors that IPTEC has for sale on our on-line store, you’ll note that every monitor we sell has both BNC and VGA connections; some monitors may carry extra connectors such as HDMI.  You’ll note that if you purchase one of these monitors they already come with VGA connectors so all you would need is a VGA cable to plug in at the DVR end and at the monitor’s location.
 
Whatever the monitor you choose to use just make sure that it is compatible with your system and beware you may have to buy a converter if you are using an older model.  It’s ironic that the DVR doesn’t need the monitor to record video yet the monitor is probably the most used component of the security camera system.
 
 
Source : http:// www. security cameraking .com/ securityinfo /

Passive Video Balun

 If you would rather use Cat5E instead of RG59 cable, it’s likely that somewhere along the way you will need a passive video balun.  IPTEC carries a full line of baluns both active and passive.  Passive video baluns help prevent the degradation of the radio frequency signal over cable.

A balun is really a specific type of transformer that can convert electrical signals that are balance about ground (also known as differential) to signals that are unbalanced (single ended) and vice versa.  The name “Balun” comes from two words, BAL(ance) and UN(balance).

For those of us that are not electrical engineers, another way to put it is that passive video baluns can boost signal strength and help your system make a transition to one type of cable to another.  For example, most cable used in the digital video security industry is RG59 coaxial cable.   This is an excellent cable for the job, however RG59 only has a working distance of about 600 feet before the signal starts to degrade causing poor video quality.

Using a passive video balun, the signal can be changed at the connection source from RG59 to CaT5E.  This is done because Cat5E is less expensive for one thing, secondly it’s easy to pull when installing it, it’s generally less expensive than RG59, and a passive video balun and Cat5E can carry a signal further than RG59 cable, usually about 1,000 to 1,200 feet.

In addition, if you do use Cat5E cable instead or RG59 you will have multiple pairs of wires at your disposal.  RG59 basically has a solid copper core wire insulated with plastic and then a metal shield (in essences the second wire) which is then covered by the cable cover (usually some type of plastic).  A digital video camera uses both of those wires the copper core and the outer shield to transmit its signals.

However, by using a passive video balun with Cat5E cable you have access to 8 (4 pairs) of (usually) 22 gauge wire.  This allows you to use just one Cat5E cable instead of 4 RG59 cables for 4 security cameras.

Many people would say they’ve never seen a balun before, but chances are they have.  Some older model TVs came equipped with a cable TV type plug and no antenna connection.  Usually, the RG59 type cable has 75 ohms of impedance.  An antenna was often 300 ohms of impedance.  An “adapter” often came with the TV with a male cable TV type plug on one end, and two screw connections on the other end to connect to an antenna.  That adapter is actually a balun, and it’s used to balance the impedance differential between the TV outlet and the antenna.

Before going any further, now would be a good time to address the “passive” in passive video balun.   Baluns may be passive or active.  An active video balun is much like the passive video balun with one distinction:  The active video balun requires power.  Usually, most active baluns use 12 VDC, the same type of power that the digital video system uses for the cameras.

Active video baluns, depending on the type, etc. like the one used in our example above of the passive balun that got 1,000 – 1,200 foot range, would be capable of boosting the signal on Cat5E upwards to a length of up to 4,000 – 5,000 feet.
 

Source : http:// www. security cameraking .com/ securityinfo /

Wide Dynamic Camera

 A wide dynamic camera conjures images of an incredibly large (In a horizontal direction) camera, somewhat like an oversized wide-angle lens.   However, that’s not what a wide dynamic camera is at all.  In fact, some ultra-small hidden covert cameras are also wide dynamic cameras.  So just exactly what is the wide dynamic range of a camera?  Read on to find out.

A wide dynamic camera is actually a camera with a highly specialized function to assist the image capture process.  When cameras possess the circuitry to support this function we say that they have Wide Dynamic Range or WDR.

The whole idea behind this business of a wide dynamic camera is to produce a superior image, at least superior when compared to the image from an exact same camera that does not support WDR.  WDR helps to provide clear video images under unbalanced, poor lighting conditions:  Specifically, when the intensity of the light varies such that that there are incredibly bright and dark areas that appear simultaneously in the field of view (which is destined to become the video image) of the camera.

Overly dark areas and overly saturated light areas, especially over saturation of back lighting is the problem that the wide dynamic camera is trying to solve.  The better the WDR of a camera the better video image produced under undesirable backlighting conditions and other over contrast conditions.

Specifically, a wide dynamic camera filters the intensely bright back light that may surround an object therefore enhancing the ability to distinguish features and shapes on the subject that were “washed” out by the intense bright light.  The dynamic range of a camera is normally defined as the ratio of the brightest point of an image to the darkest point of the same image.  Some also refer to this situation as “maximum contrast.”

In essence, what happens in this situation is the intensely bright (back) light is causing the camera to adjust itself to that particular condition.  When this happens, the video image produced is a washed out image near the light source and everything else being to dark to recognize.  This does not necessarily apply to images with steady light sources; it can occur when momentary intense light appears (for what ever reason) throwing the entire camera off balance.

Perhaps one of the best examples of a problem wide dynamic range is when a camera attempts to capture an image in front of a large storefront window.  The object inside the store appears far too dark with the sunlight pouring through the front window and washing out the details of most of the field of view of the camera.

There are several different approaches to the solution of this problem and although each method’s goal is the same result (a balanced, detailed video image) the process they use to go about correcting the situation may be different.  Basically there are two major methods or technical solutions that are used to correct the problem and there are additional methods that “hybridize” the process by combing the two basic methods.

The first solution is “multi-frame imaging.”  Here the wide dynamic camera captures more than one frame of the field of view.  Each of these frames possess their own dynamic range and the camera combines the different frames to produce one WDR image or frame.

The second solution is the use of non-linear sensors (generally logarithmic sensors) where the sensitivity level of the sensor at different light intensities also varies providing the capture of the field of view in one wide dynamic camera frame.

Combinations of the two methods just mentioned are also used. For example, they may include parallel capturing by more than one sensor using a common optical path.  Here each sensor captures different levels of the dynamic range of the scene by either different exposures, different optical attenuation in the final optical path, or different sensor sensitivity.  There are many more combination methods that may be used as well.

The key is that if you intend to use a camera that will be capturing areas of extremely high contrast or that are back lit by an extremely bright light, you’ll want a good wide dynamic camera to capture the image.

Source : http:// www. security cameraking .com/ securityinfo /

BNC Connections


Probably the most common cable joiners in the digital video security systems industry are BNC connections.  BNC connectors are easy to use and ensure a sound, full contact connection.  BNC connections are different than most other single pair wire connectors  (such as RCA plugs, for example) plugs, becuase BNC connections are “locked” in place.  The following article is about the origin and use (including applications) of BNC Connections.

BNC is an acronym for this type of radio frequency connector.  The connector is designed for use with coaxial cable and is generally used for radio, television–including digital video camera security systems, and other radio-frequency applications.

BNC stands for Bayonet Neill-Concelman.  Bayonet (“B”) represents the the type of twist locking system that holds the connectors together.  Unlike RCA plugs that just push together can be subjected to accidental disconnection, BNC connections are locked together in the same twisting lock configuration as that of a gun bayonet.   Generally, BNCs do not become disconnected unless they are purposely untwisted from the locked connection.

The “N” and “C” in BNC stands for the first letters of the last names of the two men that invented the connector; Paul Neill and Carl Concelman.  However, origin for development lies with Octavio M. Salati, a graduate of the Moore School of Electrical Engineering (of the University of Pennsylvania).  In 1945 Salati filed for a patent for a coaxial cable connector that would minimize wave reflection and/or loss (one of the primary attributes of a BNC type connector).

Another feature of the BNC connection is that the connectors are available to match the impedance of the cable they are connecting.  Generally, there are two major types of BNC connections based on impedance, 50 and 75 ohm versions that are used today.

There are also many variations that originated from the BNC design.  These include the SR-50 and SR-75 Russian copies whose dimensions differ slightly from the BNC because of converting the measurements from English (Imperial) units to metric.  There is also a Threaded Niell Concelman or TNC connector that displays superior performance over a BNC for microwave applications.

The BNC connection consists of two separate pieces, the “female” and “male” ends.   These ends are firmly and permanently attached to the shielded coaxial cable.  The male end consists of a center (usually) solid copper core wire with the metal shield or mesh that surrounds the cable completing the single pair wire connection.  The male connector is pushed into the female connector and twisted, making the single pair connection and locking the connection at the same time.

There are also different types of BNC connections based on how the actual connector is attached to the cable or provides adaptation to a BNC connector.  IPTEC offers a variety of BNC connectors on their on-line store catalog.

IPTEC offers three different types of BNC connections base on how the connector attached to the cable it is attached to and not the actual connection between BNC pieces themselves.  In addition, more many connectors they offer a single unit price and a 100 unit price.

The first of three is the crimp-on connector.  This connector requires the use of a crimping tool to secure the banded necks of the BNC to the coaxial cable.  They are referred to in our catalog as “2 Piece Crimp-on BNC Connector).  These are fairly easy to work with, and when installed properly, including being crimped properly, these provide a fair to good connection.  This BNC requires the use of a special crimping tool.

The second is the twist-on connector.  They are referred to in the catalog as “BNC Connector Twist-On.”  This BNC connection is easy to install (just twist or screw on the cable ends) and requires no special tools.  These connectors hold fairly well and provide a fair to good connection.  Screwing the connectors onto the cable ends can actually be a little difficult though.

The third type is a compression connector.  They are referred in the catalog as BNC Compression Type Connector.”  These connectors require a compression crimping tool (also sold by IPTEC) and provide an excellent connection and are easy to work with.


http://www.iptecworld.com

Source : http:// www. security cameraking .com/ securityinfo /

Closed Circuit Security Camera


The closed circuit security camera has been used for decades. But when the digital world began to affect the digital video security and surveillance world, it opened up numerous new features never available before that made this type of system versatile, powerful, and simple and easy to use.

In addition, digital cameras became lighter, circuitry came on very small Integrated Circuit Chips (IC chips), and all of these things contributed to driving prices down so that systems were much more affordable for individuals and not just big corporations or the incredibly wealthy.

Closed circuit security camera systems also known as Closed Circuit TeleVision or CCTV have evolved over the years and have come a long way technologically speaking. Older analog system cameras were pretty large and bulky, but today’s cameras are so small they can be hidden in the head of a Phillips screw!

Let take a look at the evolution of closed circuit security cameras and some of the features and options they offer today.

The original closed circuit security cameras were direct spin-offs from the television studio camera.   In the studio, the camera captured a video image, processed it somewhat, and passed it along to the editing room where any necessary changes could be made or added.  The signal was then sent through amplifiers that increased the signal’s power tremendously and sent it through a huge outdoor antenna.

Once the signal made it to the antenna it was “broadcasted” as far as the strength of the signal could go.  Anyone with a receiver, in this case a television, could “pick-up” these video transmissions and watch was being recorded.  Since the signal was just emitted in any direction and to any person wishing to view or hear it, the system was referred to as an open broadcast system (those of us that didn’t care to get too technical just called it “TV”).

CCTV or closed circuit security cameras worked on the same premise.  A video camera would capture a video image and then send it along a video transmission cable.  However, this is where the similarity ends because CCTV typically did not “broadcast” their video using an antenna.

Instead, cabling was used and was where the video image signal remained.   In order to see the video that was being captured an individual or video recorder would have to be connected to that cable.  Since all the components of the system were connected in one way or another, usually via the video transmission cable, this was referred to as a “closed circuit” hence the name “Closed Circuit TeleVision” or “CCTV” or specifically in the security industry, closed circuit security camera.

Granted, there are wireless cameras that have their own transmitter and antenna built right into the camera, but these cameras are on a special frequency and cannot be picked up with an ordinary TV.  So in essence, even though we still may broadcast security camera signals, these signals are only meant for the people that are designated to use the system.  Therefore we can “stretch” the meaning of the phrase “Closed Circuit Security Camera” to include even these cameras, since their transmitters and receivers still maintain a somewhat “closed circuit.”

In addition to wireless technology, here are just a few of the features available today with close circuit security camera:

- Night time Infrared technology.  The sensor chip in the camera is inherently sensitive to near infrared radiation as well as visible light.  These cameras can be used in conjunction with InfraRed Light Emitting Diodes or IR LEDs.  The human eye cannot see the IR LED light source, but the camera can.
- Pan-Tilt-Zoom or PTZ cameras.  These cameras can move horizontally or vertically and also zoom in on objects.
- Hidden or disguised cameras.   We sell a product (our product# HC-SCREW-W) as small as a Phillips head screw that contains a camera.
- IP ready (Internet Protocol) cameras contain their own web server technology and can be accessed by almost any computer or smartphone connected to the internet.
- Cameras with two-way audio.
- Object tracking or following.   Some PTZ cameras have the technology built right in to the camera to track or follow objects or people.

http://www.iptecworld.com
Source : http:// www. security cameraking .com/ securityinfo /

Construction Surveillance


It’s not always easy to hire an agency to provide 24 hour 7 days a week construction surveillance.  However, the need still arises because construction locations are prime targets for vandalism and theft, especially at night when the work has stopped and no one else is around.

No one particular state or city is immune.  Although most plumbing systems installed to day are plastic, there still exists some new install using copper pipe.  As the price of copper continues to raise, so will the theft from these construction sites.  Electricians install pre-wired electrical service to the construction site (such as a house, a store, or an apartment building) during the day.  At night, burglars come and rip it out so that they may take it to a scrap metal business and sell it for its weight.

So what can you do to stop or at least deter construction area theft?  You could hire an on-site security company to patrol or guard the site all night long.  This isn’t cheap, and in some localities it may be all but impossible to do.  IPTEC suggests using a digital video security camera system, tailor made for your particular construction surveillance.

Usually, when a burglar sees that someone is using digital video construction surveillance systems, that alone deters further vandalizing or criminalizing acts.  Yet sometimes things do happen even when the cameras are in plain site.

However, with today’s modern technology, you could actually set up a temporary digital video security and surveillance system to monitor your construction site.  During the day time working hours this provides great documentation for any mishaps that may lead to a workers compensation claim.  During the night time you could use a remote video monitoring service like Digital Security Guard that can alert you and the authorities the minute something is detected.

A typical construction surveillance system could include a wireless IP camera system, probably one of the quickest and easiest construction surveillance systems to install.   If you must leave expensive materials, tools, or machines at the site overnight place a camera so they are each in view.

You could also place the cameras in a perimeter configuration around the entire construction site, to help deter vandalism and thieves from even entering your construction area.  Constant monitoring of these cameras will automatically help you to determine if any unauthorized individuals are trying to gain unauthorized access to the site.

IPTEC carries a wide variety of cameras and associated equipment for just about any job.  Box cameras are an industry standard but remember that they will require housings and mounts which you must purchase separately.

Bullet cameras are ideal for this situation as they are weatherproof and quite often contain night time Infrared modes.   In this mode they use near infrared light emitted from InfraRed Light Emitting Diodes or IR LEDs.  Humans cannot see this light but the camera sure can.

Even dome cameras can be used for construction surveillance.  Here we recommend that you consider the vandal resistant models.  They are made as indoor/outdoor cameras and also can come with IR modes.  In addition, a Pan-Tilt-Zoom or PTZ camera can be mounted on each end of the cross member of a “T” shape pole and this is often all that is needed for construction surveillance.

IPTEC also has DVR lockboxes that are weather proof that can be used on site and anchored in such a way as to make it too difficult for anyone to run off with.  If you choose to use a system that requires the DVR be on site than these will be very helpful in providing a place for your DVR (and other equipment for some of the bigger models), a secure and locked place.

Construction surveillance is a positive move any way you look at it.  Serving a dual purpose of accident monitoring during work hours and security and surveillance during non working times.

CCTV Multiplexer




A CCTV multiplexer or Closed Circuit TeleVision Multiplexer allows more than on camera to be connected to the unit but only one output at a time is allowed through the unit.  Most Digital Video Recorder or DVR units have this function built right in to the DVR.  Another way to describe a multiplexer is by its function which is to combine various input signals and generate only one output signal.  You can almost think of a CCTV Multiplexer as being similar to a computer router.
For digital video security and surveillance systems, the multiplexer is what allows the display of 8 cameras simultaneously.  Eight video transmission cables from eight individual cameras connect to the multiplexer.   The multiplexer then takes the 8 individual camera inputs and combines them into one.  This how you are able to view 8 digital video security and surveillance system cameras on one monitor.
A CCTV multiplexer works by allocating bandwidth; this highly refined process insures that the transmission medium is used efficiently.  There are actually four different methods of multiplexing:
* Space division;
* Frequency division;
* Time division; and,
* Address multiplexing.
Generally speaking, digital transmission uses time division multiplexing and analog transmissions use frequency division.
In applications like cable TV each channel the user visits is broadcast on the input cable at a different frequency.  But with a CCTV application however, since the cameras are all on a closed circuit, all use the same frequency.  With each camera broadcasting at the same frequency there would be no doubt of the signals getting jumbled up, interference, and cross talk.  Literally, about the only way to handle that situation would be for every camera input to have its own monitor.  In other words, a 16 camera system would require 16 separate monitors.  CCTV multiplexers were designed to put as many cameras as possible on one monitor and reduce the user’s cost by relieving the need for the same number of monitors as there are cameras.
Multiplexers are available in a variety of sizes.  Since the DVR often contains the multiplexer, the multiplexer can be custom designed within the DVR unit itself via the manufacturer of the DVR.  However separate, external multiplexers are still available and used today in about three different configurations based on the number of cameras (channels) that are being used.  Common sizes for stand alone multiplexer units are 4, 8, 16 and 32 channels (camera inputs).
Setting up a multiplexer is rather easy and doesn’t require much prior knowledge of digital video security systems.  Some multiplexers do have a few different features that you will need to activate if you want to use them.  These may include the ability to view one channel at a time or all or multiple channels at the same time.  Some units may also have a “dwell” setting.  Dwelling is the term applied to multiplexers that describes the ability to display a particular camera for a certain period of time before showing the next cameras.  This process is repeated cyclically as the multiplexer moves through each individual camera one at a time.  This is also known as “dwell time.”
Some CCTV multiplexers not only can dwell, but some also come with a hand held remote control that allows the user to stop or move-on a particular camera in the system.  Setting the multiplexer up for use with these features is usually accomplished with On Screen Displays or OSD that make the set even quicker and easier.
In the past, CCTV multiplexing was not an option but was a definite requirement if you wanted to see more cameras than just one on a monitor.  Today, with LCD and LED monitors multiple camera viewing is very easy.  Now the only question is how many cameras do you want to view at once?  Of course this is dependent on your DVR which ultimately means, dependent on the multiplexer built into your DVR.

Source : http:// www. security cameraking .com/ securityinfo /

Saturday, July 2, 2011

Zoom CCTV

 
One of the most popular digital video security system features is the zoom CCTV or Closed Circuit TeleVision. There are many different types of Zoom CCTV cameras designed for a multitude of uses; be sure when shopping for one that you get the features you need. What is a “zoom CCTV” anyway? It’s a digital video security camera used in CCTV that can vary its lenses focal length enough to enlarge objects farther away from the camera and make them appear closer (enlarged) and with more detail. These lenses are often referred to as varifocal. Most box cameras that do not have built in lenses so they have the advantage of using Zoom CCTV lenses only. These can be manual lenses where they are basically positioned through trial and error by hand or they can be remotely controlled as well. There are also some cameras that do have on-board lenses that zoom only and these are often found among the bullet type and dome type cameras. When we say “Zoom” only, we are referring to just the zoom function, as compared to a Pan-Tilt-Zoom or PTZ camera which has additional features including the ability to move horizontally or vertically.

Source : http:// www. security cameraking .com/ securityinfo /

TVL Camera Resolution

Digital video security cameras come in all shapes and sizes and with different degrees of resolution, often using the phrase “TVL Camera” such as a 600 TVL Camera. What does TVL mean and how does it relate to digital video security cameras?  We’ll answer that question and more in the following article.

First, It will make things much easier to understand if you know a little security camera industry history. Full security camera systems have been around for several years now, however not until relatively recently have the systems been based on binary (digital) data instead of its older analog data.

In the old days, (a few years back), security cameras were in a closed loop with an analog recorder, such as the older VHS or Betamax video recorders. Recorded security footage was either recorded on a looping video tape, so that when the tape reached its end it would start at the beginning recording new material over the previously recorded older data. Another method was to monitor the Video Recorder closely (and constantly) and eject the current tape when full and insert another blank tape (probably the least favorable of any of the methods).

The point here being that video security systems have been around for a long time, doing most all of its work based on an analog system and not a digital system. When Personal Computers became poplar and started creating all sorts of devices that could be digital instead of analog, the security video industry certainly wasn’t the last to be affected. Today, nearly all video security systems that are sold are DIGITAL video systems.

As the “digital age” came upon us, the security camera industry started assimilating advanced technology and digital based devices with just one problem. Sometimes the industry adopted the new digital nomenclature yet other times they would maintain the old analog nomenclature. So, TVL camera is actually a carryover from the analog days.

A TVL camera is referring to the detail it can display in different formats. It represents the horizontal lines of resolution that the camera is capable of displaying. Older CRT (Cathode Ray Tube) monitors and televisions created a picture by flashing a moving beam across the screen, usually about 60 times per second. TVL represented how many times the CRT would draw a horizontal line. The greater the number the more detail on the picture.

TVL camera carried over from the analog days and is still used today. However, today’s cameras are digital and produce their images by creating tiny dots that are circular or square called pixels. This is how the Digital Video Recorder or DVR displays its images. However, there is still some confusion, because the specifications for the DVR refer to the size of the image being recorded, not the detail. To make matters more confusing, they use a mixture of different terms. For example:

- D1 is the same as 720 x 480 pixels
- CIF is the same as 360 x 240 pixels
- 4CIF is 704 x 480 pixels

And these are usually the terms referenced in regard to what size image the DVR will display from a given camera; once again this is not detail but how big of a display it can create. However, TVL can be applied to these because TVL is the resolution or detail in each of the above examples. This means that a D1 camera/DVR combination should be able to display up to a size of 720 x 480 pixels with a 520 TVL camera. However, if the TVL camera produces a resolution higher than what the DVR can support, the detail resolution information is lost or in other words just not used.

For example, if a DVR displays the image in CIF format, using a 540 TVL camera is basically overkill because CIF format can only support about 280 TVL, the rest is wasted. Be certain to consider these picture sizes and resolutions when designing your system because you’ll want everything to match up.


Source : http:// www. security cameraking .com/ securityinfo /