Video signal
Most cameras have a standard composite video output signal (described as 1Vpp 75 Ohm).
You can directly connect camera output to the TV or a video recorder. This is
the best choice, cheap and widely used. Because it uses an analog
signal, you need an extra equipment to connect it to a computer, but
in most cases it is not necessary – you can use standard video
monitor. Video to USB converter costs about
50&euro
, TV or video PCI cards
are even cheaper. There are other solutions, like firewire or even RS-232. I see no any reason to use firewire, maybe if you want to use video camera with firewire input as monitor. I expect only problems when using firewire, especially with maximum length of the connection cable. One (and the only) good thing about an RS-232 camera is that you can plug it directly to the computer. The very bad is that it can provide only 3 frames per second! This is right solution if you like to watch static images. PowerMany cameras are powered by 12V, some 5V. Consumer video cameras (VHS, DV, Hi8) needs the same voltage as its batteries, e.g. 7.2V. If your robot is powered by 12V try to choose 12V camera. For other voltages you need voltage converter. ResolutionResolution of CCTV cameras is defined by number of lines (TVL). More lines means more details on the screen. Typical values are from 320 to 470 lines. There are cameras with 600 lines but use it only if you have unlimited budget. LensA very important part of the camera. For most CCTV cameras you need to buy lens separately. Parameters of lens worth to mention:
Sensor
There are two types of sensors: CCD and CMOS. All cheap cameras have
CMOS sensor. More expensive and consumer video cameras have CCD
sensor. Most important parameter of sensor is sensitivity. This is
minimum amount of light that camera needs to proper work. Less number
means better parameter. 0.1lux – very good, 1lux – average, 3lux –
rather bad. Note that some cameras have Sensitivity 0lux. It means
they can work in infrared range and thus you need an extra infrared
lamp. Black and white sensors have usually better sensitivity then
color ones. What to chooseI bought 2 cameras:
There 3 options you can consider:
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