Thermal Myth No.8 ~ 'Thermal imaging cameras are easy to damage, and expensive to repair'

Thermal imaging cameras may be sophisticated but they are certainly not delicate – at  least they shouldn’t be, if you buy good quality models. The key point to remember is that thermal cameras were developed by manufacturers such as FLIR for military and government applications, therefore robustness was built-in at the earliest stage of their evolution.

When working with thermals, certain rules for care need to be followed (see point 7 about wipers, for example) but if you buy good quality units from leading suppliers you will get years of trouble-free life.

The key is to specify the best grade equipment; thermal cameras are undoubtedly more expensive than conventional units, so make sure you get the quality that you’re paying for.

Myth No.10 ~ 'There is no complete IP CCTV system available'

The market has developed rapidly, with manufacturers racing to develop the best IP CCTV equipment. All the hardware and software you need are now available.

Over recent years, a number of system gaps have been identified. PTZ cameras, particularly for external use, have not been readily available, and the control of PTZ cameras with joysticks has not been possible. Transmission distances have been limited to the 100 m achievable over Cat 5 cable, and video matrices with multiple monitor outputs have not been available.However, as IP systems develop at a frantic pace, these limitations are being overcome.

Excellent PTZ cameras for internal use are available now, and fully functional cameras for external use are being launched at all the main CCTV shows. Videoservers can also be used to provide high quality IP images from good analogue PTZ cameras.

The leading manufacturers now offer joystick control of their PTZ cameras, in which the joystick is
connected to the network like all other devices.

Fibre is leading the way in extending transmission distances. And, because optical fibre is electrically transparent, fibre optic transmission can be used even in the vicinity of heavy electrical plant. This means that Ethernet signals sent over fibre can be used where traditional coaxial cables could not, both as a means of extending transmission distances, and as a means of overcoming electromagnetic interference.

Video and data can be sent up to 4 km using multimode equipment, and a massive 30 km or more using single mode equipment.

Good software enhances IP systems, and well priced software is now available to view live and recorded images from multiple devices. Advanced features such as mapping allow camera locations to be seen easily, and the images from those locations can be brought to screen quickly by clicking on the camera item on the map.

Thermal Myth No.7 ~ 'Adding a wiper improves operation in difficult conditions'

There are several reasons why adding wipers to thermal imaging cameras is not a good idea, not least increased cost and reduced product life-span.

Most importantly, the highly sensitive Germanium lenses (the kind used in the best FLIR thermal units) may be damaged by repeated wiping, as grit and other tiny particles will typically be trapped between the wiper and the lens surface. Even the hard carbon coating which protects most FLIR camera lenses may be scratched by repeated mechanical wiping – think of using a scouring pad on a top quality non-stick pan!

In fact, wiping is really not necessary at all. Most of the time the sharpness of a thermal image will not be affected by a light build up of dirt, salt or water droplets on the lens. In very dirty conditions occasional, manual cleaning may be desired. This can be done quite simply by hosing the unit down from a distance – the cameras are well-sealed, and will not be damaged by this method of washing.

Myth No.9 ~ 'I will get a data loss if an IP product fails'

Network-based systems can offer greater protection against failure than old analogue technology, as long as systems are built using reliable components from reputable manufacturers.

Analogue systems can go down too if a camera, recorder or other key component fails. The way to minimise this risk is to choose reliable equipment from a leading brand, and to consider some duplication of equipment in critical positions. IP CCTV systems are no different, and the same principles apply. IP systems are more readily viewed in multiple locations – even remotely - and, consequently, any equipment failures can be spotted more easily.

It is important to use reliable network components. Those with experience of home PC networks will know how ‘flaky’ some domestic equipment can be, particularly wireless equipment, often needing a reboot to come back into operation. In most domestic situations this can be frustrating but not critical. Security systems are, of course, a different matter, and care should be taken to choose professional, ruggedised equipment, particularly for sensitive applications. In short, the equipment should be selected for the environment – for example, use field-hardened products
for non-air-conditioned areas.

IP has some other tricks up its sleeve, including network cameras with the capability of recording a loop of back-up information to an SD card or similar removeable media. This means that if there is a temporary problem at the recorder, backup information is also recorded at the camera.

Thermal Myth No.6 ~ 'Thermal imaging cameras can’t see through fog or rain'

Thermal imaging cameras can see through light fog and rain – but their performance is certainly reduced, and the worse the weather conditions, the poorer the visibility becomes. Having said this, in many foggy conditions, thermal imaging continues to offer improved image captured when compared to standard CCTV cameras. System planners are used to taking account of occasional poor performance in the visible part of the spectrum due to bad weather, and the IR image capture is no different. Unlike conventional CCTV, thermal cameras are not hampered at all by smoke or changing light conditions.

In planning a surveillance system it has to be remembered that thermal imaging cameras can’t see underwater or through glass because the infra-red heat is disrupted. So heavy fog and rain will reduce image resolution – exactly how much, depends on a range of factors, including the size and temperatures of the target object and the temperature of the surrounding environment. There are also many different types of fog, with different sizes and densities of water droplets (aerosols). For example urban and rural fog tends to be much less of a problem than marine fog. System planners need to take all these factors into account.

Myth No.8 ~ 'IP CCTV systems are not secure'

With all their data encrypted, secure IP networks are more robustly protected than analogue systems ever were.

It is important to ensure that the correct security measures are in place. So long as the right protection is used (including firewalls, VPNs and password protection), the internet can safely transfer all kinds of sensitive information. Any system is only as strong as its weakest link, so anyone using a public network for video transmission should secure their data traffic using VPN technology.

Banks and financial institutions have paved the way in using the internet as a medium for global money transactions, helping it to develop as a proven medium for other secure applications including IP CCTV. Analogue surveillance systems are less secure than the new digital technology, because they have no encryption or authentication of information. It is very easy for third parties to tap into the cables of an analogue system and gain access to supposedly secure video transmissions. This cannot be done with secure IP networks.

Thermal Myth No.5 ~ 'Thermal imaging cameras require expensive and complicated cooling systems'

This is not true: thermal imaging cameras operate in two frequency bands and cooled systems are only need for higher quality images in one of them. In practice, un-cooled units, which work in the longwave infra-red band (LWIR) do the job perfectly for most commercial applications, including high security ones. This is because LWIR is the wavelength where most terrestrial temperature targets emit most of their infra-red energy.

Un-cooled cameras have fewer moving parts and typically a longer working life with less down time. Cooled cameras operate in midwave infra-red (MWIR) and  cost two-to-three times as much as un-cooled cameras. Of course they may be the required choice for specialist applications (notably where the range is greater than 5km) but for most commercial security situations the extra expense is not warranted as un-cooled cameras give great images under most operating conditions.

Myth No.7 ~ 'Remote monitoring of IP CCTV is not possible'

IP systems are designed to allow both active monitoring and passive viewing. In fact, IP is making remote
surveillance more feasible for all levels of application.

Remote monitoring is different from remote viewing. Remote viewing is the observation of live and recorded images on a PC, usually over the internet, and usually through the PC browser. Some devices may require FOC software downloaded on the PC for remote viewing. Open standard and proprietary software is also available for purchase with enhanced features and the facility to look at multiple remote devices on the same screen.

With IP, so many more things are possible. Although upload speeds are still limited over the internet, the
ability to view images remotely is a fantastic facility made possible by IP. It enables business owners check
the security of their premises remotely, and allows business managers to confirm that remote branches
are operating as they should without the need to travel there.

Remote monitoring is done at a remote central station using specialist software by companies geared up to
receive images against an alarm, and to respond accordingly. Images are generally uploaded to the
monitoring station against an alarm that an operator can review and record and then act on by contacting
the police, a private security company or the business owner as appropriate.

Because the monitoring station is continually monitoring its remote sites, it is often the first place where CCTV system faults are spotted - for example, if a camera is down and not transmitting images. Also with IP, it is possible to check camera and recorder settings, and perform fixes and upgrades remotely. In this respect, partnering a forward-thinking monitoring station not only enables your CCTV system to be monitored cost- effectively, but can also help with the maintenance of the system.