The difference between photographic shutter and slow door

Dude, your concept seems a little vague.

Shutter usually refers to pressing a button that can take pictures. And the shutter is divided into several grades and slow door, which refers to the speed of the shutter. Different cameras have different shutter speeds and gears.

For example, the early film machines are generally B, 1/2, 1/4, 1/8,116, 1/30, 1/60. Usually, slow shutter speeds such as 30 seconds, 20 seconds, 15 seconds ... 1/2... 1/30 are all called slow doors, that is to say, all slow shutter speeds can be called slow doors. How to divide this file?

Hehe, I am speechless, too ...

Agree with the shanzhai statement.