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Security cameras need to capture clear images at night or in extremely low light conditions, so you can use a lower ISO for your camera.

1. What is illuminance?

Illuminance is expressed in Lux, a unit of illuminance that measures the light sensitivity of a camera, meaning how dark the lighting conditions the camera can capture images in. The lower the Lux value, the clearer the image the camera can capture in lower lighting conditions. Usually, the prescribed value of the video signal generated by the camera is 1V, and the standard value is 700mV. For example, when using an F1.2 aperture, if the illumination condition is 0.02Lux, the camera's output video signal amplitude is 33% to 50% of the standard value, and the camera's minimum illumination at this time is 0.02Lux/F1.2. It is important to note that lenses with different apertures support different minimum illumination values. WEILAILIFEI's wireless surveillance cameras are equipped with Smart HDR technology, which makes the image quality even clearer. HDR is an abbreviation for High Dynamic Range. Simply put, it is a function that allows you to take beautiful photos even in backlit or dark places by combining multiple photos with different brightness. To put it in textbook terms, "It is a technology that can express a wider range of brightness (dynamic range) compared to normal shooting (SDR/standard dynamic range).

2. Solutions for low-light photography

Ordinary CCD cameras are divided into two types: color and monochrome, and different types of cameras have different minimum illumination levels.

A typical color camera's CCD chip has three color filters, red, green, and blue, which means that the color camera cannot sense infrared light, whereas a typical monochrome camera has a wider spectral range and can sense not only visible light, but also infrared light.

To capture clear images in low light, engineers typically use solutions such as:

(1) Normal low-light monochrome CCD camera + infrared light

Infrared lights are installed in the surveillance area, emitting infrared light that is invisible to the human eye but can be picked up by cameras, allowing for nighttime photography.

(2) Color/monochrome switchable camera + infrared light

This type of camera operates in color mode during the day, but automatically switches to monochrome mode when necessary in low light conditions, taking advantage of the monochrome mode's higher infrared sensitivity to work in conjunction with infrared lights.

(3) Infrared low-light color camera

These cameras have 4 times higher infrared sensitivity than ordinary cameras and can operate in 0 lux illumination conditions. WEILAILIFEI home security cameras are equipped with IR-CUT function, which automatically switches to day/night mode according to changes in light, providing clear color images during the day and sharp monochrome images at night.

(4) Slow shutter camera

Slow shutter cameras store multiple frames in succession in the computer and accumulate those images to produce a clear image. These cameras can shoot in 0.008Lux/F1.2 illumination conditions and are suitable for places where infrared and ultraviolet rays need to be avoided, such as museums, night wildlife observation, night military surveillance, etc.

(5) Ultra-low light camera

The ultra-low light camera uses EXVIEW HAD technology to greatly improve sensitivity, allowing it to shoot in illuminance conditions of 0.05 Lux in color mode and 0.003-0.001 Lux in monochrome mode. Combined with a dedicated infrared device, it can capture high-resolution monochrome images in 0 lux conditions. WEILAILIFEI's security camera set also has improved sensitivity at night, so even if you cut out the infrared rays, you can still see most of the area with just the light from the outdoor lamp.

Under low light conditions, different types of cameras and lighting equipment can capture clear images, meeting various surveillance needs. WEILAILIFEI provides high quality surveillance solutions to ensure your surveillance equipment can achieve excellent performance in various lighting conditions.