When we use SONY FCB cameras or other cameras, we often consider the problem of focal length, which is also a lot of people use DSLR cameras to think about, so what is the focal length of the camera?
A simple explanation is that focal length, also known as focal length, is a measure of the concentration or divergence of light in optical systems, referring to the distance from the center of the lens to the focus of light concentration.
How to choose the focal length in the SONY FCB camera? We have a lot to think about.
Under normal circumstances, under the monitoring environment of ordinary conference rooms, offices, elevator rooms, a short distance prime lens of about 3mm to 12mm can meet the needs. If the security monitoring in the community, or ordinary road monitoring, 6mm to 15mm monitoring lens can basically meet the needs.
For general intersection monitoring, due to the large shooting space and high clarity requirements, it is suitable for a mid-distance focal length lens from 6mm to 60mm. A wide range of cameras used for urban security monitoring, due to the difference in monitoring distance and environment, basically configure a long-distance zoom lens of about 10mm to 120mm.
If used in highways, national highways, rivers, airports, forests and other areas with large area monitoring needs, in these environments, the monitoring range is far from the main characteristics of these environments, so the general selection of 10mm to 1100mm lens to meet the shooting needs.
In addition, in the imaging characteristics of the lens, the larger the focal length, the farther the monitoring, but the smaller the observation Angle, the smaller the focal length, the nearest monitoring distance, the larger the field of view Angle; It is therefore a contradictory relationship in which distance and Angle are the only options.
Therefore, when choosing the focal length size, it is often measured according to the Angle of view of the shooting. However, too large or too small initial focal length may have a certain adverse effect on the monitoring effect.