How to buy surveillance cameras?

Lens is an important part of camera, and the photosensitive elements of camera are generally divided into CCD and CMOS. In photography, CCD design is often used because of its high requirements, while the camera does not have such high requirements for images, so CMOS applied to lower images can meet the needs.

Moreover, a great advantage of CMOS is that its manufacturing cost is lower than that of CCD, and its power consumption is much smaller. In addition, you can also pay attention to the size of the lens. The bigger the lens, the better the imaging quality.

2. Pixels

Pixel value is an important index that affects the quality of the camera and also judges the performance of the camera. At present, the pixel value of mainstream products is generally around 300 thousand.

But it doesn't mean that the higher the pixel, the more suitable it is for us to use, because the products with higher pixel value need more extensive data exchange, so we should choose according to our own network situation. Generally speaking, a 300,000-pixel camera is enough.

Step 3 solve

Resolution is the ability of a camera to analyze and distinguish images, which is closely related to the selection of photosensitive elements. In practical application, the standard of 640x480 can meet our application, and the product with high resolution is more expensive. There are also some cameras whose resolution of logos is realized by software, which has a certain gap with the hardware resolution. Be sure to pay attention when buying.

4. Focus function

The focusing function is also one of the most important indicators of the camera. Generally, a good camera should have physical focusing function, so that we can manually adjust the focal length of the camera and get the clearest image as far as possible.

5. Additional software

Many friends think that brand-name products are expensive and uneconomical. In fact, although brand-name products are more expensive, the supporting software allows you to maximize the application scope of the camera and make it worth it. And the performance of brand-name products is not bad, so we still suggest you buy brand-name products with more software to maximize the function of the camera.

6. Price

Price is the most concerned factor when people buy. At present, cameras with a size of 100 ~ 200 are the most competitive in the market. Almost all the core photosensitive chips are controlled by several manufacturers, so everyone is on the same starting line in this respect.

COMS is a common photosensitive chip in the market, which is adopted because of its low price. However, the CCD mentioned by merchants in the market is still unrealistic at present. Lenses are also an important factor affecting the price. Some cameras use plastic lenses in front, and glass lenses are better.

Step 7 show up

Most users who use cameras are young netizens who like chatting online, and some of them use it to contact relatives and friends in different places, so they also attach great importance to design, which is why there are so many different shapes on the market. Models with eyes, astronauts and cameras are really varied and dazzling.

8. Performance

The shooting quality and transmission speed of the camera in common environment jointly determine the use effect. Bian Xiao wants to remind everyone here that the performance of the camera should not be too bad. You'd better connect the computer to do the test at the scene. At the same time, it is also affected by pixel factors, and the image quality of high pixels is also high.

At present, the pixels of mainstream products on the market are mostly 300,000-350,000 pixels, and the price is naturally rising. Swing your hand quickly left and right in front of the camera to see if the displayed image is smooth. A good camera should have clear images, bright colors and no smearing.

9, installation and use

The camera is connected to the computer through USB interface, and the driver needs to be installed. As long as you follow the instructions, ordinary users can also install it themselves, as long as the manufacturer provides qualified installation instructions. Maintenance is a long-term problem, because the camera structure has been relatively fixed and can only be upgraded in software.

Well-known manufacturers can provide system upgrades, and users can get more technical support through software-driven upgrades. Therefore, Bian Xiao suggests that you buy cameras of famous brands, such as Logitech, 00 1, Mesh, which is undoubtedly more attractive to users. One thing you should remember is that the brand is the guarantee of your purchase.

Extended data:

1, divided by the imaging color.

(1) color camera: It is suitable for distinguishing the details of a scene, such as clothes or the color of the scene. Because of the color, the amount of information increases, which is generally considered to be 10 times that of black and white cameras.

(2) Black-and-white camera: suitable for areas with insufficient light and areas where lighting equipment cannot be installed at night. When only the position or motion of the scene is monitored, a black-and-white camera with a resolution usually higher than that of a color camera can be selected.

2, according to the camera resolution.

(1) The image pixel is about 250,000 pixels, the color resolution is about 330 lines, and the black-and-white resolution is about 400 lines.

(2) The image pixels are between 250,000 and 380,000, the color resolution is 420 lines, and the black and white resolution is below 500 lines.

(3) The image is more than 380,000 points, the color resolution is more than or equal to 480 lines, the black-and-white resolution is more than 600 lines.

3, according to the camera sensitivity.

(1) Normal type: the illumination required for normal operation is 1~3 lux.

(2) Moonlight type: the illumination required for normal operation is about 0. 1 lux.

(3) Starlight type: the illumination required for normal operation is below 0.0 1 lux.

(4) Infrared illumination type: In principle, the illumination can be zero, and infrared light source is used for imaging.

4. According to the size of the CCD target surface of the camera element.

The size of (1) 1 in the target plane is 12.7mmX 9.6mm high and the diagonal is 16mm.

(2) The size of 2/3 inch target surface is 8.8 mm× 6.6 mm high, and the diagonal line is 1 1 mm. ..

(3) The dimensions of the target surface 1/2in are: 6.4 mm in width, 4.8 mm in height and 8 mm in diagonal.

(4) The dimensions of1/3 inch target surface are: 4.8mmX in width, 3.6mm in height and 6mm in diagonal.

(5) The size of1/4in target surface is 3.2mmX wide, 2.4mm high and 4mm diagonal.

(6) 1/5in is under development, and the official product has not yet been launched.

5. In addition, CCD cameras can be divided into PAL system and NTSC system, and can also be divided according to image signal processing mode or camera structure area. Points.

References:

Baidu encyclopedia-monitoring camera