What is a focal plane? What's the difference with the general lens?

Focal plane is a kind of photographic lens specially designed for shooting high-quality videos and movies. They record continuous motion and provide excellent video quality, which is very suitable for film production. Compared with the general lens, the focal plane has the following differences:

1. The focal plane is more resistant to operation than the ordinary lens, and most of it is made of solid all-metal material, which also ensures that the daily small bumps will not damage the optical components inside the lens.

2. The focus ring of the focal plane is different from the ordinary lens. First of all, you can see that there are many teeth on the focus ring. These jaws are designed to be combined with following focusing. Different from still photography, when shooting a movie, you need to focus during the shooting process. In many cases, it is impossible to focus manually when the camera is placed on the stabilizer. At this time, it is necessary to follow the focus wirelessly. Follow-up focus is fixed on the lens, a pinion is clamped with the focus ring on the lens and transmits wireless (or wired) signals at the same time, and a special follow-up focus component will follow the focus beside the photographer.

3. The T aperture of focal plane is more accurate than the F aperture of SLR.