How to set the Nikon d850T door?

How to set the B door of Nikon d850 camera? The setting method is as follows:

The B door of Nikon camera, the so-called B door, refers to the B shutter, that is, B(Bublesetting), also known as manual shutter. Gate B generally has a long exposure time, such as shooting a star track; Or it is used when the traffic of night photography needs to wait for multiple exposures covered by black cards.

Press the shutter in the range of m, and the shutter opens to start exposure; When the shutter is released, the shutter closes to stop exposure. In other words, the time of each exposure is determined by the length of the shutter pressing time, and the exposure time can be controlled more freely.

The "B" door of the camera is an important function, which can not only solve the exposure problem, but also play a special role in photography creation, and has functions that other shutters cannot achieve. Use M gear, set the shutter to slow down, and door B will end.

First, turn the OK dial to the dot position 2, press the button in the middle of the AF/M dial, turn the main dial to select AF-S3, press the button in the middle of the AF/M dial, and turn the auxiliary dial to select 5, thus realizing the single-point focusing mode with variable focusing position in the autofocus mode.

AF-S: After pressing the shutter for half a time (without releasing) to focus, the machine will not refocus if it is re-composed. This is what is often said: "Focus first and then compose". AF-C: it can be called sports focus mode. After the shutter is half pressed to focus (not released), the composition is completed again. As the focus has changed, the machine will refocus.

This mode mainly shoots moving objects, such as moving cars. When your lens is chasing a car, the focal length changes at any time, so you need to stay in focus until you press the shutter. AF-A: This model is actually a combination of the former two. The machine will judge for itself whether you need to focus with AF-S or AF-C. ..