If the environmental conditions are supportive, and you need color video images even at night, a color day night camera is your most likely solution. These cameras require no InfraRed Light Emitting Diodes or IR LEDs to light up their field of view. Therefore the video image retains its original color even in conditions with almost no visible light what so ever.
Digital video security cameras, especially the color day night camera, are amazing pieces of technological wonder. They have plenty of positive benefits and are the ideal choice for security and surveillance systems today. Let’s take a look at how a typical digital video security camera and system work.
In an effort to keep things simple we won’t get into the detail of the system but we will consider details pertaining to the camera. A digital video security and surveillance system normally consists of three separate, independent components, the camera, the DVR, and the monitor.
The cameras’ job is to capture reflective light and convert it into electronic information that can be sent to the DVR for processing or to a spot monitor for viewing. The DVR’s function is to control the system, store the digital video file, and display the results of the cameras on a monitor(s). The monitor, of course, displays the end result, the video image.
The camera alone is basically an electronic wonder. The digital video camera today is very similar to the analog video cameras of yesteryears except that it is cheaper, lighter, and much more versatile, uses less power, and can be incredibly small in size. This is how a typical digital video camera works.
First, the camera has a field of view, an area of which is subject to capture by the camera. In the field of view, objects reflect light, which is gathered by the camera’s lenses, and focused on a small sensor chip that is usually 1/4 to 1/3 inch square.
There are two different types of sensor chips. Both provide the same end result (a digital image) but each goes about providing the end result in different ways. The two chips are called a Charged Coupled Device or CCD and a Complementary Metal Oxide Semiconductor or CMOS. The light from the lenses is focused at this chip which is photo sensitive. When light strikes the chip, a small but measurable electric impulse is given off. By manipulating the impulse values appropriately the camera can construct a video image.
Interestingly, the initial video image data is analog. The data is run through an analog-to-digital Integrated Circuit (IC) Chip that converts the initial analog data into binary or digital format. Most cameras also have a processor called a Digital Signal Processor that further refines the image and makes any fine tuning adjustments before leaving the camera.
What is most interesting is that both sensor chips the CCD and the CMOS are inherently sensitive to infrared radiation in the near infrared portion of the electromagnetic spectrum. Usually there is a filter that is removed for normal night time recording because if the cameras pick up both bright visible light and ambient infrared light during the day without the filter the image it produces is distorted in some way or another.
Color day night cameras may use other filters only at night too. These cameras also contain highly sensitive CCD and/or CMOS chips such that with the high sensitive chip, good lenses, and just a small bit of ambient light (a starlit night for example) the can produce a color digital video image. Incidentally, the empahsis here on color is important because IR based video image are either black and white or monochromatic, but they are never in color because colored light is out of the bandwidth range for near IR.
Often times these cameras’ over all sensitivity to light (lens, filters, sensors all play a part) is rated for the camera in Lux. A color day night camera may be rated to work and continue to produce high quality color video images down to 0 Lux conditions.
It’s important to note that these cameras are not producing an infrared light based image. Therefore IR illuminators are not required and the natural color of the image is retained and reproduced.
If you have any questions concerning color day night cameras, please contact one of our security experts either via on-line “Live Chat” or by telephone. They will be happy to help you with any aspect of your system.
