With the increasing crime rate in society, the role of infrared surveillance at night is becoming more and more outstanding. Not only the important departments such as treasury, oil depot, ordnance depot, library, cultural relics department, prison and so on are selected, but also in the general surveillance system. Infrared cameras are also used in residential TV surveillance projects. This shows that the use rate of infrared waterproof camera is getting higher and higher, and it has gradually developed into a trend.
Dongying Security Company Shares Attention to Selection and Purchase of Infrared Waterproof Camera1.给出摄像机较低照度的一起，还要给出光圈F的要求值，而变焦镜头一般只给出1:F的较大值，即光圈F的较小值（光圈实践尺寸较大值），F=f/D,那么D为定值，在f焦距拉大10倍时，F变得很大（即光圈实践尺寸变得很小）。
1. Give the minimum illumination of the camera together with the required value of the aperture F, while zoom lenses generally only give the maximum value of 1:F, that is, the minimum value of the aperture F (the maximum aperture practical size), F = f/D, then D is the fixed value, when the f focal length is increased by 10 times, F becomes very large (that is, the aperture practical size becomes very small).
2. When active aperture lens, active gain control or active electronic shutter camera are used, the F value of lens aperture will also change. For example, when there is a scene near the camera, reflecting strong light back to the camera, or when there is a light illuminating the camera nearby, the sensitivity of the camera will be reduced, the size of the active aperture will be reduced, and the luminous flux will be greatly affected.
3. The minimum illumination given by the camera. What is the concept of minimum illumination here? The nominal value of the video signal generated by the camera is 1V and the standard value is 0.7V, while the minimum illumination of the video signal is 1/3-1/2 of the standard planting. So the picture of the camera at the lowest illumination will never be "the same as the day".
4. The protective shield also affects the effect of infrared lamp. During the transmission of infrared light, the transmittance and reflectivity are different through different media. Different windows, especially active defrosting coated glass, have different attenuation to infrared light.
With the rapid development of infrared night vision system for infrared waterproof cameras, infrared light manufacturers will add it. But red light products are not as easy as some people imagine. The conditions in technology, testing equipment and other aspects are also different. We expect users to make more comparisons and make steady choices. Users using infrared waterproof camera infrared lamp first need to carefully read the instructions, especially in order to ensure the safety of personal equipment. Check whether the above mentioned aspects of compatibility meet the requirements, should take into account the impact factors, if not meet the requirements, can adjust the equipment used in a timely manner.
Users should not privately improve the supply voltage, because infrared waterproof camera infrared lamp design, not only take into account the full use of its irradiance, but also consider its safety and reliability. The improvement of power supply voltage may cause the burning of infrared lamps, let alone the private dismantling of infrared lamps. If this is done, the manufacturer may no longer be servicing. If there is a problem with the infrared light of the infrared waterproof camera, contact the manufacturer or supplier.
5. The clarity of the picture when the camera is in the lowest illumination is measured by the TV signal test card. The black and white stripes require that the black reflectance be close to 0% and the White Reflectance be greater than 89.9%. But we sometimes do not have such conditions when we observe on the spot. For example, the reflectivity of leaves and grasslands is very low and the contrast is very small, so it is difficult to obtain a clear picture.