3rd Eye Surveillance Systems Protecting People, Property and Profits
							Digital Video Recorders
		Understanding Digital Security Cameras & Security Systems Camera selection is an important part of your system.  It is the eyes into what is being monitored.  There is a camera for just about every situation you can think.  Let’s start with camera basics.  Almost all cameras purchased these days are digital verses analog.  A digital camera focuses light from a lens onto a computer chip that is sensitive to light.  There are two types of chips CMOS and CCD.  CMOS has fewer light receptors than CCD chips.  Less expensive cameras use CMOS chips.  High-resolution cameras use CCD chips.  All POM Technologies cameras are CCD cameras. How important is the resolution? That depends on what you are using the camera for.  If you want to see fine details such as facial features or images on a cash register display then a CCD camera is a must.  In general expect that a black and white CCD camera will start at $125 retail including a lens on the CCD camera body.  Everything below that price is likely to be a CMOS- based camera.  CMOS chips are used in low-end products such as web cameras you can attach to your PC.  They provide a good picture for relatively short distances (up to 15 feet) and good light levels (all interior lights on). If you are using the cameras for commercial security (like watching for theft) then a CCD camera is a must. After resolution the type of lens you use is an important choice.  Two important factors affect how well the lens works; the iris and lens diameter. Iris An iris controls the amount of light that passes through the lens opening.  Auto-irises adjust the opening based on changes of light in a room.  This is similar to the human eye.  An auto-iris is very important in areas where the lighting changes such as rooms with exterior windows or rooms with variable lighting. Lens Diameter The lens’s opening size (its diameter) affects how wide and long the field of focus is.  Diameter is represented in millimeters (mm).  The larger the diameter the narrow the field but the longer it is.  So you want a lens with a low diameter (such as 2.6 mm) for a room about 40 by 40.  But a large diameter (such as 8 mm) would be great for focusing on a distant door. Low-end cameras come with integrated lenses that have both a fixed iris and a fixed diameter.  Higher-end cameras have separate lenses that must be purchased or variable lenses. Digital Security Camera Types •        Black and white security cameras. Inexpensive cameras that work well in high and low light conditions. •        Color security cameras. Inexpensive cameras that work in general working light. •        Covert security cameras. These cameras are so small they cannot be easily seen or are disguised as a different device (such as smoke detector, clock or teddy bear). They have a short distance of focus and poorer resolution. •        Day/Night security cameras. These cameras switch from color to black and white depending on lighting levels. They are ideal for variable lighting conditions. •        High-resolution security cameras. These cameras have extra light sensors on their digital chips. They increase the effective image quality. This type of camera is only effective with high- resolution monitors. •        Infrared security cameras. These cameras have their own light source in a light spectrum that can’t be seen by the naked eye. These cameras are ideal for small areas with no light. •        Outdoor security cameras. These cameras have hardened, waterproof outer bodies. •        Pan, Tilt, Zoom security cameras. These cameras allow for remote control of what the camera is pointed at and what it is focused on. •        Vandal Proof security cameras. These cameras come in hardened cases that can resist the toughest physical abuse.