There are universal cameras in the security area of the computer city, and the price is not expensive, ranging from 200 to 500. Selection method: 1, and determine the focal length. Generally, 3.6 6 10 12 mm lens is used indoors (to put it bluntly, it is the choice of viewing angle range. If the space is narrow (for example, 10 square meter room uses 3.6mm lens, so the viewing range is large; ) You can also choose the lens by area. 2. Is there an infrared function (generally used indoors) 3. Choose between analog and HD. The latter will be more expensive, but the definition will be much higher. Now it is a trend that HD replaces analog. 4 brand selection, commonly used brands are: Dahua, Hikvision and other well-known domestic brands, which are more expensive than other miscellaneous brands.
There is also a home wireless HD camera. There is no network cable, so you can use the WIFI at home. This machine can be stored or stored in the cloud, and can be monitored in real time with a mobile phone. With infrared alarm function, after protection, when someone breaks in at home, the pictures taken at home can be sent to the mobile phone immediately.
There is a lot to say. I don't know if you understand. I hope I can help you.