When it comes to monitor your home the quality of your CCTV camera is extremely important and the footage captured by your surveillance system will only be as good as the camera itself. You can determine the quality of the camera by several factors like focal length, field of view, resolution, lighting and weather resistance.
To ensure you get the most out of your CCTV cameras and have an understanding of it works we have gathered for you few optics principles.
The Focal Length
The focal length is the distance between the center of a curved lens to its optical center when focused at infinity. This sets up how far and wide your camera can see expressed in millimeters. A larger focal length number means that angle will be narrower and a smaller number indicates a wider view.
Short focal length provide wider angle with more detail but less clarity at greater distances while longer ones offer more focused views over greater distances with fewer details but increased clarity.
Security cameras usually come in either 4mm or 6mm lens sizes. A 4mm lens can see up to 20ft away from its point of origin while a 6mm lens captures footage up to 120ft away which makes it great for monitoring driveways or front entrances.
Field Of View
Field of view means what you can see through the camera horizontally and vertically. It’s measured in degrees and wide angle lenses are usually 2.8mm or 3mm. A 4mm lenses cameras offer an angle of 62 degrees with an approximate line of sight of 100ft while 6mm lenses have an approximate line of sight range up to 120 feet away .
Resolution
The resolution or image quality captured by your camera is determined by pixels per square inch. The higher this figure is the sharper and clearer the image will appear onscreen and anything up to 8 million pixels per square inch should provide excellent results. Common resolutions found on security cameras include 2MP (megapixels), 4MP ,5MP ,and 4K Ultra HD (high definition).
Some Other Factors
In addition to these considerations that affect how clear and how far your camera can see other factors like lighting within an area being monitored, infrared lighting for night vision and weather resistance like fog or rainstorms should also be taken into account as well. Buying high quality equipment does not guarantee perfect results but getting the best possible set up certainly increases chances for success
