Which cable is used for video surveillance?

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Everything to do with video surveillance, video technology, surveillance cameras and security.


What types of surveillance cameras are there and for which situations are they suitable in each case?

 

Boxed-type surveillance cameras

Boxed-type cameras get their name because of their typical, rectangular shape. The cameras can usually only be used on their own indoors. With accessories such as different housings and lenses, however, the range of applications can be significantly expanded, which makes this design very popular for individual special solutions. Boxed-type cameras are available as analog models, but also as IP cameras.

 

Fixed dome cameras

Fixed dome cameras - also known as "mini domes" - are compact camera solutions with a dome housing. This type of camera benefits from an inconspicuous, unobtrusive design as well as the difficult-to-see recording direction. In addition, the dome-like design of the camera housing offers effective protection against deflection and defocusing. This type of camera is not movable, such as PTZ dome cameras

 

PTZ dome cameras

Thanks to extensive functions for panning, tilting and zooming, PTZ network dome cameras cover a large area and enable relevant areas to be enlarged. PTZ dome cameras support functions such as B. Configuration and automatic storage of tour monitoring, audio, inputs and outputs for external alarm devices, gatekeeper function, auto-tracking and platforms for intelligent applications. An extensive range of accessories is often available for PTZ dome cameras, which significantly increases the field of application.

 

Bullet style cameras

Cameras with a "tube" shape are commonly referred to as bullet-style cameras. Bullet-style cameras are often equipped with numerous features by the manufacturer, such as infrared LEDs, light-sensitive lenses or special firmware. These cameras are designed to cover a wide range of surveillance needs. The difference to box-style cameras is that this type of camera can usually no longer be converted to meet more specific requirements.

 

 

Panoramic cameras

If a large area has to be permanently monitored, panorama cameras with a 360 ° field of view are the first choice. These cameras can be used to monitor large areas for activity, track flows of people and improve space management.

 

Remote head cameras

A characteristic feature of remote head cameras is the separation of the main unit from the sensor unit (the actual lens). With this design, only the sensor unit has to be installed in the area to be monitored, the rest of the camera can be stored in a physically separate location via a cable connection. In this way, discreet and covert surveillance can take place. Typical areas of application for remote head cameras are shops, hotels, offices, banks and ATMs.

 

Board cameras

Circuit board cameras (also called camera modules) are suitable for inconspicuous, concealed surveillance due to their particularly small form factor. They are fully-fledged cameras without a housing and specially developed for installation and integration into existing systems or housings. Due to their small dimensions, they are very versatile. In addition to video surveillance, the small camera modules are also used in industry for control and monitoring or in robotics for drones or UAVs.

 

Thermal imaging cameras

Thermal imaging cameras are the ideal addition to professional IP surveillance systems with which areas or properties have to be secured in complete darkness. Images of objects, vehicles or people are generated with the help of the outgoing thermal radiation. For this reason, this type of camera delivers images even in complete darkness with which the operator of the video surveillance solution can identify suspicious activities at an early stage and take appropriate measures.

 

equipment

Whether the network cameras are installed in demanding outdoor areas, on ceilings, walls or in corners, or are used for nighttime surveillance - choosing the right accessories is important so that all requirements are met and installation is quick and easy.

 


Factor light sensitivity in surveillance cameras

 

Surveillance cameras face a particular challenge. They always have to deliver usable images and are exposed to a wide variety of lighting conditions. Such conditions are often found in a high-contrast scene in which very dark shadows and light areas meet. For this reason, the light sensitivity of a surveillance camera is crucial for the possible field of application, as well as the quality of the images.

The light sensitivity is also referred to as the minimum illumination. It defines the smallest amount of light that the camera needs to generate a usable image. The unit of measurement for illuminance is given in lux (lx). Basically, the more light there is in the scene, the better the image quality. If there is too little light, the picture begins to be noisy or is too dark. How much light is needed to achieve good image quality depends on the camera and its sensitivity to light.

Overview of lux and lighting conditions
brightnessLighting conditions
100,000 luxStrong sunlight
10,000 luxBright daylight
500 luxOffice lighting
100 luxDimly lit room

 

Video surveillance despite poor lighting conditions?
Day / night cameras

There are different approaches to ensure usable video surveillance even in poor lighting conditions. One possibility would be the use of so-called day / night cameras. If the light falls below a certain value, these surveillance cameras automatically switch to near-infrared light and produce high-quality black and white images. You can find more information about day / night cameras on the Axis Communications homepage.

Additional lighting

Another solution is the use of additional LED lighting. With headlights specially developed for video surveillance, a completely dark scene can be optimally illuminated, so that the use of cameras without day / night mode and without particularly high light sensitivity is possible without any problems. Our long-standing partner Raytec has specialized in the field of LED lighting and offers a full range of infrared and white light LED emitters for CCTV and security-related applications. More information about the products at https://www.rayteccctv.com/

Infrared cameras

The use of thermal imaging cameras is also useful. Especially in complete darkness, with haze, dust or fog, these special surveillance cameras provide easy-to-use images. The images from thermal imaging network cameras are generated using the thermal radiation emanating from objects, vehicles or people. Most security camera manufacturers also offer infrared models. However, one manufacturer has specialized exclusively in thermal imaging cameras. The US company Flir offers a wide range of products in this area.

Contrasting scenery

As mentioned at the beginning, areas with dark and very light areas are a challenge for surveillance cameras. Often an area is overexposed and details can no longer be seen. See image:

Image source: http://www.axis.com/de/de/learning/web-articles/wide-dynamic-range/what-is-wdr

Axis Communications offers a solution to this problem. Many surveillance cameras from the global market leader support the so-called WDR function (Wide Dynamic Range). Thanks to this feature, the camera can display a high dynamic range between the darkest and lightest areas of a given scene. See image:

Image source: http://www.axis.com/de/de/learning/web-articles/wide-dynamic-range/what-is-wdr

What factors affect the light sensitivity of surveillance cameras?

There is no worldwide standard for measuring methods for light sensitivity. In principle, every manufacturer therefore conducts its own tests for the minimum lighting of the respective camera models. However, this also means that customers have to rely on the information provided by the manufacturer, which can often lead to mistrust.

In order to be able to correctly assess the performance of a camera in low light, it is advisable to test it yourself and at best to compare it with other models. In low light it is also important to test moving objects in the scenery.

The sensitivity of a camera to light depends on many factors that can be manipulated. There are many factors that affect the camera's sensitivity to light, such as: B .:

  • Exposure time
  • Focal ratio of the lens
  • Size and quality of the sensor
  • Lens quality
  • Color temperature

Network cable

Network cables physically connect the stations or participants in a network. There are different network cables that differ in material and structure.

Patch cord

Patch cables are cables that connect patch panels to network end devices. They are available in fiberglass and also in copper. The copper patch cord cores consist of flexible copper strands, whereas the fiber optic patch cords usually use more flexible zip cord variants.

Twisted pair cable

Twisted pair cables are copper cables with twisted wire pairs. These Network cable are used for signal and data transmission, especially in telephone and network technology.
The twisting in pairs and an electrically conductive screen reduce disruptive influences, and the overlapping between adjacent pairs of wires within the cable is also reduced.

This electrically conductive screen is wrapped around the wire pairs and consists of an aluminum foil or a wire mesh. The wire mesh serves to shield against low-frequency fields. However, a combination of both has proven to be very effective because it reduces internal and external electromagnetic influences.
There is an antistatic plastic film between the wire mesh, the metal foil and the wire pairs in order to reduce the static charge caused by friction.

Twisted pair network cables also have different names:

descriptionproperties
UTP
  • Plastic sheath containing unshielded, twisted pairs of wires
  • Easy to process, install and inexpensive

 

S / UTP

 

 

 

 

 

F / UTP

 

SF / UTP

  • Plastic sheath + overall shield, in which there are twisted pairs of wires
  • Shielding made of copper braid and / or aluminum foil
  • Very high quality

 

 

  • Overall screen made of foil only

 

  • Overall shield made of foil and wire mesh
U / FTP
  • Plastic jacket and twisted pairs of wires surrounded by a metallic foil screen
  • PiMF (pair in metal foil) each surrounded by a pair of wires with metal foil
  • ViMF (four in metal foil) of two pairs surrounded by metal foil
  • Processing + laying more complex
S / FTP
  • Plastic sheath and twisted pairs of wires
  • Wire pairs surrounded by a metallic foil
  • Wire pair bundle surrounded by an overall screen made of wire mesh
F / FTP
  • Plastic sheath and twisted pairs of wires
  • Wire pairs surrounded by a metallic foil
  • Wire pair bundle surrounded by an overall shield made of metallic foil
SF / FTP
  • Plastic sheath and twisted pairs of wires
  • Wire pairs surrounded by a metallic foil
  • Wire-pair bundles surrounded by an overall screen made of wire mesh and a metallic foil

 

Network cables from Axis Communications

It often happens that Network cable which are not at all suitable for the desired area of ​​application.

In the case of outdoor video surveillance installations in particular, the wrong components are often bought and processed. Network cables that are not suitable for outdoor use cannot withstand extreme weather fluctuations and associated temperature fluctuations as well as aggressive UV rays in the long term. These cables include simple patch cables.
Only a small part of the plastic that is used in these cables is sufficiently light- and weather-resistant. That is why many products must also be provided with active carbon black. Active carbon black is the best light and weather stabilizer to date. Strong weather fluctuations can change the appearance in terms of shine, color and cracks, but also the chemical composition and the usage properties such as chemical aging and radiation resistance.

Axis offers a special network cable which can withstand installation outdoors at any time.

Installation of network cables

When wiring and installing network cables, particular care must be taken to ensure that they are handled with the utmost care. Network cables should only be stored and installed in dry rooms. In addition, it should be ensured that network cables are separated from power cables, i.e. the cable duct should be separated with a separator. In addition, if the pressure and tension are too strong, the quality and physical properties can be reduced. In the case of twisted pair network cables, it must be ensured that the twisted wires are not opened too far or are twisted again, this can lead to poor values ​​in measurements.

Network cable categories

Network cables are offered in different categories, these describe the respective capabilities of the individual Network cable. The cables of the higher categories automatically cover the performance parameters of the lower categories of network cables. Of course, specific and binding requirement criteria have been defined for each category.

Categories 5-7 (Cat 5 to Cat 7) are standard today. However, there are categories from 1-7. The cables of categories 1 and 2 are no longer important in practical use.
Cat-1 cables were previously used for operating frequencies of 100 MHz or less and were only used for telephony.
Cat-2 cables are suitable for operating frequencies of 1.5 MHz or less. They were widely used for home wiring.
Category 3 and 4 cables are rarely found in old installations today, but they are no longer in use in practical applications. Cat 3 LAN cables were suitable for operating frequencies of up to 16 MHz, Cat 4 network cables were suitable for frequencies of up to 20 MHz.

 

categoryTypefrequencyapplication
Cat 5UTP100 MHz100 BASE-TX and 1000 BASE-T
Cat 5eUTP100 MHz100 BASE-TX and 1000 BASE-T
Cat 6UTP250 MHz10 GBASE-T
Cat 6aSTP500 MHz10 GBASE-T
Cat 7S / FTP600 MHz10 GBASE-T, CCTV, telephone
Cat 7aS / FTP1,000 MHz10 GBASE-T, telephone, CATV

 

Network cables in video surveillance

The high resolutions (1080p & 4K) of modern video surveillance systems mean that ever larger amounts of data have to be moved over the video network. In this context, the quality of the network cables is of particular importance. Therefore, if you are planning a video surveillance system, you should not skimp on the quality of your network cables.

Network cables and latency

Please note that with IP video surveillance systems there is a delay in the live playback - also known as latency. This latency is usually between 0.3 and 0.7 seconds and depends on the selection of the network components (network cable, switch, router) and the hardware for playing the live stream.


PoE - Power over Ethernet

PoE is a standardized process in which network end devices are supplied with power via a network cable. This is often used in video surveillance.

PoE has already become a leader in security networks and local network cabling. Power-over-Ethernet eliminates the need for a separate power connection.

The biggest advantage, however, is that the existing network cabling with twisted pair cables can be retained. When developing the PoE standards, the physical limits of the network cables were taken into account.

IEEE 802.3af / Power-over-Ethernet (PoE)

This standard applies only to 10BASE-T and 100BASE-TX. Therefore, only wire pairs 1/2 and 3/6 are used for data transmission, the other two wire pairs remain unused. Therefore, the unused wire pairs are often used for the power supply.
The maximum power consumption is 15.4 watts per switch port. However, due to the heat development, one assumes a usable power of 12.95 watts with 100 meters of cable.
This power is sufficient to supply IP telephones, handheld computers and economical notebooks with power.

IEEE 802.at / Power-over-Ethernet-Plus (PoE +)

With this standard, PoE for 1000Base-T is also suitable. In addition, the performance is almost doubled; Cat5e / 6 cables are recommended due to the high performance. In the end, a usable output of 21.90 watts can be expected.
There is still no real purpose for PoE +, since PoE devices with 10 or 100 Mbit / s are completely sufficient for standard use.

IEEE 802.3bt / Four-Pair-Power-over-Ethernet (4PPoE / PoE ++)

The special thing about 4PPoE is that all wire pairs are used for power transmission. This increases the power to 70 to 100 watts. 4PPoE can operate a complete computer with screen including telephone via a single cable. This avoids tangled cables.

It is also important to mention that there is a limit to the total PoE power. Therefore, the power consumption and power consumption of a single PoE device should be measured to avoid possible damage.

Energy supply - endspan and midspan

There are two variants of the energy supply, on the one hand the endspan process and on the other hand the midspan process.

The Endspan process is a direct supply through a PoE switch.
The IEEE 802.3af standard describes a consumer, the Powered Device (PD). The power supplier is the Power Source Equipment (PSE), in most cases this is a PoE switch, which is responsible for the power supply. This process is known as the final chip removal process.

With the midspan process, on the other hand, the supply takes place via interconnected sources.
Several switches are supplied with PoE via a special solution. For most devices, a simple power injector is sufficient, which is connected in the line network between the switch and the outgoing network line to the end device, such as a surveillance camera. A Power Hub is recommended for multiple PoE end devices.

Energy supply - phantom supply and spare pairs method

Phantom power is provided when all wire pairs of a network cable are used. This means that the current is superimposed on the data signal.

With the spare pairs method, the two unused wire pairs are used for the power supply. This separates power and data. This method is often used with 100Base-TX and 10Base-T.

The IEEE 802.3af and IEEE 802.3at standards differ here. With the IEEE 802.3af standard, only the unused wire pairs are used for the power supply. With the IEEE 802.3at standard, however, all wire pairs are used for power supply.


Installation of a surveillance camera - what should you watch out for?

Whether or not a video surveillance system works properly depends on how the surveillance cameras are installed. Accordingly, this step is particularly important.

 

Define monitoring goals

First of all, it should be determined which monitoring objective will be pursued. Is a large area with a lot of movement monitored, narrow alleys or corridors, areas with difficult environmental and lighting conditions? The surveillance situation can place a wide variety of demands on the surveillance cameras and the VMS. Find out whether the cameras to be used meet the requirements. The manufacturers provide all the necessary information for this, such as degrees of protection, lux values ​​or temperature ranges.

 

Power supply and data transmission

The location of a video surveillance system determines how the cameras can be supplied with power and how the data is transferred. In large areas with distances of well over 100 meters, e.g. the power supply via PoE reaches its limits. In areas where there is no network infrastructure and new cables cannot be laid, WLAN cameras are also used. Before buying and installing the surveillance cameras, it is therefore particularly important to clarify all questions about the infrastructure and the structural environment.

 

The right lighting

It is often sufficient to install surveillance cameras with integrated IR lighting or with a day / night function. However, an inexpensive alternative can also be the use of external light sources. Headlights specially designed for video surveillance are available for both indoor and outdoor use. The scenery can thus be optimally illuminated even in complete darkness and allows the identification of important details, such as face or license plate recognition. For this purpose, our partner Raytec offers a highly professional range of spotlights tailored to video surveillance.

 

Sunlight factor

The direct effect of sunlight on the camera and the image sensor can enormously reduce the quality of the video images. To avoid this, the camera should be mounted so that the sunlight is best behind the camera.

 

Back light

Especially at night, cameras are blinded by different light sources. Avoid installing the surveillance camera in front of mirrored and reflective surfaces. Such a surface could be a window, for example. If it is not possible to install it in another location, simply pulling the curtains or blinds can help. Basically, it is recommended to use cameras with a large dynamic range for scenes that have strongly changing lighting conditions. Surveillance cameras with a large dynamic range are better able to deal with backlighting situations.

 

Adjust camera settings

After installing and commissioning a surveillance camera, manual settings may be necessary in many cases, e.g. to adjust the focus or the image section. If the cameras were installed in locations that are difficult to access, it is advisable to make the basic settings immediately after installation. In the case of network cameras, fine-tuning and settings can be made directly on site using a WiFi-enabled installation device. Two of our partners offer such devices. Axis Communications with the T8415 and Veracity with the Pointsource.


 

Assistance in choosing a network camera

A few years ago, IP cameras were still in the minority in the field of professional video surveillance. Today they clearly dominate the industry landscape. Current developments in technology and society also suggest that the number of network cameras used will continue to increase.

This development is followed by an ever-increasing range of IP cameras. More and more manufacturers are entering the market and the established companies are also constantly expanding their product portfolio.

The following points are intended to help you choose the right network camera.

1. Define monitoring objectives: overview or detail

When monitoring a large scene, especially movements of people and objects can be reliably identified. In the case of detailed images, the areas to be monitored are smaller, but the cameras can capture more details. For example, the identification of faces, license plates or POS terminals is in the foreground. The surveillance target basically determines the field of view and the position, as well as the type of camera or lens required.

Be clear about what exactly the surveillance camera should detect / record. Here are some examples of monitoring objectives:

The surveillance camera should:

  • Take detailed shots of faces
  • Detect movement over a large area
  • Record license plates in great detail
  • Deliver clear images at night
  • Track objects automatically
Monitoring areas

After you have specified a location for monitoring, you should subdivide it into "monitoring areas". Let's assume a large shopping center. A possible monitoring location would be the entrance, for example. The individual monitoring areas would be e.g. doors, escalators, as well as elevator or stair access. The distance and number of areas to be monitored are important factors when choosing the right type of camera:

Fixed or PTZ camera?

An area can be covered by several fixed cameras or a few PTZ cameras. The advantage of the PTZ camera is the large optical zoom and detailed images. At the same time, the PTZ function enables the camera to cover a larger area than fixed cameras without PTZ function. However, in order to effectively and permanently cover this area, PTZ cameras must always be operated by one person or an automatic "tour" must be set up using a VMS (video management software).

2. Power supply and network functions

The power supply can also be different for cameras. Most modern network-compatible surveillance cameras can be operated using PoE (Power over Ethernet), which makes additional cables for the power connection superfluous and can simplify installation.

What does your camera have to do in terms of network functions? Here, too, there are a wide variety of factors:

  • HTTPS encryption for encrypting video streams
  • IP address filters that allow or deny access to specified IP addresses,
  • IEEE 802.1X for authentication over a network
  • IPv6 and WLAN interface

 

3. Open interfaces and application software

Are you planning to couple your surveillance cameras with other systems, such as alarm systems or access control? Make sure that the network camera contains open interfaces and offers a wide range of integration options with other systems. Also, make sure that the camera is supported with a variety of application and management software to facilitate installation and updates.

4. Price and quality

Another important point when choosing an IP surveillance camera is the long term. So trust brands. Established companies have been in the market for many years and often have a higher product quality (if you buy cheap, you buy at least twice). Consider manufacturers as long-term partners, because you will have to make use of services in the future so that your video surveillance system is always up to date. A manufacturer should always be able to offer the following services:

  • Support
  • Updates
  • Long-term implementation
  • innovation
5. Event management and intelligent video

Your surveillance cameras and the associated VMS should support extensive event management functions. This not only saves bandwidth and storage space, but also extends the recording time and at the same time relieves staff. The simultaneous management of several cameras by one operator is no longer a problem.

6. Photosensitivity and degrees of protection

Indoor and outdoor areas make different demands on a surveillance camera. Outside there are, for example, strongly changing lighting conditions. Cameras that can display high contrasts and have day / night functions are to be preferred. In many cases, additional lighting is also necessary to properly illuminate an image.

Important: The LUX information from the various manufacturers cannot be compared with one another, as there are no uniform industrial standards for measuring light sensitivity.

Dust, rainwater, the effects of violence through vandalism and much more can disrupt or paralyze the operation of a camera. To prevent this from occurring, all cameras have IP protection classes. Make sure that your camera fulfills the right protection class and that it can also be used outdoors without any problems.

7. Other factors

Other possible points can influence the choice of the right IP camera:

  • Open or covert surveillance
  • Which resolution is desired / necessary
  • Compression
  • Must be recorded with audio

A precise analysis of the surveillance situation and the desired requirements is essential in order to find the right camera models for your video surveillance system.