What kind of camera has better night vision?

There are about three kinds of camera night vision. As for which type of camera has better night vision effect, you can choose a high-definition infrared camera to get a clear black and white picture at night. You can also choose a low-light full-color camera to shoot a clear color picture. You can choose the type according to your needs. The following are the characteristics of night vision of three cameras. What kind of camera has better night vision?

Generally, there are three modes: infrared night vision, full-color night vision and starlight camera.

1, infrared night vision

The infrared camera at night can automatically switch between day and night. During the day, the monitoring screen presents a color mode. When the light is bad at night, the device will automatically switch to infrared mode. In infrared mode, the monitoring screen is black and white. In addition, the infrared light of the infrared camera is weak, so it may not be found if you don't pay attention to observation. Low price, it is the mainstream type of night vision surveillance camera at present.

2, full color night vision

There are two kinds of full-color cameras: full-color cameras with white light source and full-color cameras without white light source, commonly known as black light level cameras. A full-color white light source camera will automatically turn on white light when the light is dim, thus presenting a full-color picture. Black light level cameras can present color pictures in low light level environment without auxiliary light source. The monitoring picture is full-color effect, and the picture is true. Higher price and clear color images at night are the future development trends of night vision surveillance cameras.

3. Star camera

The biggest difference between starlight camera and ordinary infrared surveillance camera is that starlight camera can present color pictures in weak ambient light without any auxiliary light source. Without infrared light or white light, clear color monitoring can be realized at night without tailing.

Principle of night vision surveillance camera

Night vision surveillance cameras generally use infrared night vision cameras. The working principle is that in the dark environment without visible light or weak light, infrared light is actively projected onto an object by an infrared emitter, and the infrared light is reflected by the object and then enters the lens for imaging.

The infrared camera illuminates the object through the infrared lamp, and the infrared diffuse reflection is received by the monitoring camera to form a video image. Just like lighting with a flashlight in the dark, a flashlight is equivalent to infrared rays, and a camera is equivalent to human eyes. The reason is the same. At this time, what we see is the reflection of infrared light, not visible light. At this time, we can take photos that are invisible to the naked eye in the dark environment.

How to see the night vision effect of surveillance camera

1, look at the noise

Similar to SLR cameras, surveillance cameras usually have little or no noise during the day when there is plenty of light, and the picture quality is very good. But at night, the light gets worse and the noise increases. Noise not only affects clarity, but also consumes network and storage space in vain, increasing the pressure on the processor. Therefore, many companies have developed noise reduction algorithms to erase the noise, but the disadvantage is that they also delete the details of the picture.

2. See if day and night are equally clear.

When the light is dim to a certain extent, the camera will switch to the infrared fill light state. However, we found that many network high-definition cameras work well in the daytime. After switching to infrared, the picture clarity drops immediately, even greatly. The reason for this phenomenon is that the bands of visible light and infrared light are different, which leads to inconsistent focus. In view of this situation, some manufacturers have developed the technology of day and night focusing.

3. Look at the shadow of drag and drop

Anyone who has used a camera knows that taking pictures at night can prolong the exposure and increase the brightness, but once the picture moves, there will be obvious smear, and monitoring is more about shooting dynamic processes than static pictures. Many manufacturers deliberately set their cameras to long exposure and aim them at static objects, so the picture is very effective. But once used in real life, the effect will be greatly reduced. Therefore, we need to check whether there are moving objects dragging under night vision.

4. Look at optical adaptability

The practical application environment of surveillance cameras is complex and diverse. If there is strong light in the picture (flashlight, car high beam), will the infrared switch? Once switched, it means that there is no infrared fill light at night, the monitoring is half white and half black, and the details can't be seen clearly.