What camera in the movie has to change the light bulb as soon as it is shot?

The kind of camera in the movie that changes the light bulb at a beat. This is a spotlight camera.

The flash used in early photography was made of magnesium powder, so it was called magnesium light. Now it has been replaced by electronic flash. At present, both optical cameras and digital cameras use electronic flash. Spotlights use magnesium bulbs, which are disposable. After taking the photo, you have to change it quickly. At the earliest time, bulk magnesium powder (a mixture of magnesium and oxidant) was used. The intensity of light depends on where it is placed. The ignition of magnesium powder is made of flint used in lighters, and the wheels of flint mill have clockwork. Flash synchronization means that people wind up, pour magnesium powder, press the shutter with one hand and operate the trigger of flint wheel with the other, and it is synchronization at the same time. ?

Later, magnesium was made into filaments and sealed in a light bulb, which contains two electrodes like a light bulb. When the tungsten wire (or carbon wire) is electrified, the tungsten wire is heated and burned, thus igniting the magnesium wire to emit light. This is called a single flash bubble, which can be used once and thrown one at a time, and the flash synchronization can be realized through the synchronization switch of the camera. It was still in use until the 1950s and 1960s. Later, the flash was invented 10 thousand times (that is, this kind now) before it gradually withdrew from history.