The basic tool to aid drivers backing out of a parking space, garage, or driveway are mirrors, that are supposed to help them visualize the area behind them. However in practice the basic rear and side view mirrors have blind spots and it is rather impossible to look over both shoulders at the same time. This creates constant risk of hitting somebody or something that couldn’t be seen or running over something that could damage a tire.
Nowadays many car models have a rear view camera and a dashboard screen already installed when you buy them and their owners can enjoy the increased visibility, comfort and safety they provide. But so can the owners of older cars. However, the market offers such a vast selection of various equipment that the driver who wants to make his life safer and easier in fact faces a new problem – what to chose.
There are several important features that should be considered before buying a rear view set for your vehicle.
View angle – can range from 30 to 180 degree. Of course the bigger car the wider view angle requires – obviously for HGV – 180 degrees.
Image quality – The system should have the capability to produce a ‘mirror’ or ‘reverse’ image. It is either the camera that can produce ‘mirror’ image, or the monitor can reverse the image in order to let the driver see the same image he would see in the rear view mirror, which is best for safe operation. Some systems don’t have this option, in others both the monitor and the camera can switch from ‘straight’ to ‘mirror’ view. Never consider buying a system that doesn’t have the feature.
Another important image quality feature is influenced by the type of image sensor in the camera. There are two main types of image sensor – CCD (Charge-Coupled Device) and CMOS (Complementary Metal Oxide Semiconductor). When compared to CMOS cameras, CCD cameras have higher resolution, lower system noise, brighter night vision, higher system complexity, faster uniform shuttering, and a higher price. The CMOS cameras can be bough around Ł30. Another factor that affects the image quality is the overall resolution. The higher the resolution, the clearer the camera image is – a camera with either a 420 TV Line or a 480 TV Line should be high enough to provide a descent image.
Infrared night vision also tends to be very crucial in near or total darkness, when even the CCD camera fails to ‘see’. When the background light drops to a level that’s too low for the image sensor to produce a high quality picture a high quality night vision equipped camera turns the infrared LEDs lights on automatically.
The automotive power source you chose for your system will determine how well and how long it will work with your vehicle. Make sure the camera system you chose includes voltage regulator or filtering circuit, which will prevent the constant varying voltage produced by the vehicle’s electrical system to either damage the system, or at best, produce serious variations in picture quality. Almost all rear view camera systems will work on any vehicle that operates from 12 volts DC. However, there are exceptions to this rule, therefore some rear view camera systems can work at a variety of voltages, usually either 12 to 24 volts DC, or 12 to 32 volts DC.
Wired or wireless option for many buyers seems to be an easy choice in favor of the latter, mostly due to their relatively simpler installation process. Yet we must remember that wireless rear view cameras rely on radio frequencies, which is why they can easily be affected by radio interference. Wired rear view cameras may be a little more challenging to install, but provide much more stable and reliable signal.
The rear view camera mounting system is another feature to be chosen cautiously and mostly depends on your vehicle. There several options – box surface mount, keyhole flush mount, license plate/frame mount, mini embedded, side view style – some can be mounted in or on every component of the rear of your car. License plate frame mounting is the easiest and least invasive method , but different mounting methods work better for different vehicles.
Appropriate housing of the camera is very important for the protection of your camera. CCD cameras can be fairly pricy, so make sure they are housed in a durable, protective fashion when you install them on your car. Every camera housing is marked with International Protection, or IP code ratings to indicate how protective the housing is against agents like dust and water. Ratings of IP 66 or IP 67 should protect your camera from everything except most severe storms. Of course you must remember that even the best waterproof camera may not resist the influence of water eternally. Therefore make sure of two things while installing your camera – the cable connections have additional sealing and the wire coming from the camera is facing up and not down – just to be on the safe side.
The monitor you select for your color rear view camera system should be a TFT LCD (thin film transistor liquid crystal display) monitor if you have a color rear view camera. Another type of monitor is CRT (cathode ray tube) monitor, which is mostly used for black and white old technology rear view cameras. The LCD monitors are usually available in 5″, 7″, 9″ and 10″ screen sizes, of which the TFT-LCD type is the best. The bigger the monitor, the higher the price. For heavy vehicles like trucks, tractors or RVs, 7” and bigger monitors should be chosen to provide adequate detail for safe backing. You also need to check the power input range of the monitor – choose the one with a free power input between DC11~32V, which protects your LCD monitor from being burnt by the fluctuation of the vehicle power.
With a rear view camera you don’t have to use limited mirrors and dirty windows to see behind your car – you can see a wide field of view behind your car and determine whether or not it is safe to back up. Best of all, rear view cameras are now available on the market for relatively inexpensive prices. Just make sure you are buying a camera that is big and powerful enough to fit the size of your vehicle and to serve your specific preferences as a driver.