Three doubts about photographic flash

1. Of course, the flash flashes when taking pictures (actually when the shutter is open), otherwise it is meaningless. This is called flash synchronization.

2. Front curtain synchronization and Hou Lian synchronization are two forms of slow synchronization: when shooting with a flash, the flash flashes to illuminate the subject at the moment when the front curtain is opened, and then the Hou Lian is closed to complete the exposure, which is called front curtain synchronization. When Hou Lian is synchronized, the flash does not flash after the front curtain is opened, but it will flash and complete the exposure before the Hou Lian is closed. Slow synchronization is a form of flash synchronization.

3. After the shutter is opened, it flashes to ensure sufficient illumination of the object; The front curtain synchronization and Hou Lian synchronization have special functions: the front curtain flash synchronization flashes first. If there are moving scenes and people in the picture, the image just taken will be blocked, which is mainly used to take pictures with clear subjects when the light is dim.

Hou Lian synchronization is used for objects that want to express motion. The process is basically like this: open the Hou Lian synchronously, open the shutter to pull out a series of moving images, and finally turn on the flash to freeze the main body. Finally, the frame is very clear, with a series of shadows in front, showing the movement with special effects.

Another question is puzzling. Maybe you are talking about using the studio flash, and the modeling light will be turned off at the moment of flash.

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