Resolution selection
Camera resolution of indicators to assess the level of resolution, in units of line pairs, the number that can distinguish between the black and white image pairs. Common resolution monochrome camera is generally 380-600, 380-480 color is, the greater its value, the sharper image. General surveillance occasions, with 400 lines or so black and white camera to meet the requirements; cameras with 600 lines to get a clearer picture. Such products fully meet the medical image processing and other special occasions.
Imaging sensitivity
Often used to indicate the minimum ambient illumination requirements sensitivity of the camera, black and white camera sensitivity is about 0.02-0.5Lux (lux), color camera and more in 1Lux more. 0.1Lux surveillance cameras for ordinary occasions; when used at night or in low light environments, it is recommended to use 0.02Lux camera. When used in conjunction with near-infrared light, must also use low-light cameras.
In addition the sensitivity of the camera and lens are also relevant, 0.97Lux/F0.75 equivalent 2.5Lux/F1.2 equivalent 3.4Lux/F1 reference environment illumination: Summer sun 100000Lux cloudy outdoor 10000Lux television studio 1000Lux from 60W lamps 60cm Desktop 300Lux indoor fluorescent 100Lux indoor 10Lux 20cm evening candlelight at night Streetlights 0.1Lux 10-15Lux
Electronic Shutter
Electronic shutter time between 1/50-1/100000 seconds, the camera's electronic shutter is generally set to automatic electronic shutter mode automatically adjusts the shutter time can dim the brightness according to the environment, to get a clear image. Some cameras allow the user to manually adjust the shutter time to adapt to some special applications.
External synchronization with external trigger
Synchronization means between the external video device using the same type of synchronization signal to ensure synchronization of the video signal, which can guarantee the type of video signal output apparatus having the same frame, the line start and end time. To achieve external synchronization, the camera needs to enter a composite sync signal (C-sync) or composite video signals. External synchronization does not guarantee that users get a complete continuous from the specified time frame image, to achieve this functionality, you must use some special camera with external trigger function.
Spectral response characteristics
CCD devices made of silicon material, is sensitive to the near infrared spectral response can be extended to about 1.0um. Response peak green (550nm), the distribution curve as shown. Covert surveillance at night, you can use the near-infrared light illumination, the human eye is unclear environmental conditions, but on the monitor can be clearly imaged. Since the CCD sensor surface with a layer of transparent electrodes UV absorption, so insensitive to ultraviolet CCD. Red, green, blue three-color filter of the color camera imaging unit, so the color camera for infrared, ultraviolet insensitive.
CCD chip size
CCD imaging commonly used sizes 1/2 ", 1/3" and so on, the size of the smaller volume imaging camera can be made smaller. In the same optical lens, the larger the image size, the larger the field of view. Chip Specification imaging plane size (width X height) diagonal 1/2 6.4x4.8mm 8mm 1/3 4.8x3.6mm 6mm camera lens buying guide on how television monitoring system according to the site being monitored environment, the correct selection of the camera lens is very important because it directly affects the surface to be monitored after the effect of the painting system components on the system to see the end of the monitor system can meet the design requirements (display range or the purpose of the image details), the correct optional camera lens can make the system has been designed to optimize and get a good monitoring results.
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