When recording with multiple cameras at the same time, there may be a deviation of several frames between cameras due to factors such as camera clock and component deviations, aging, and the ambient temperature at which they are used.
Due to the complex interplay of these factors, it is difficult to give a specific amount of deviation, but as a general guideline, if you record for more than 8 hours, there may be a deviation of about 1 to 2 seconds.
Synchronous recording is a method that completely eliminates the above deviations and makes recordings without deviations. Synchronous recording uses not only a camera, but also a synchronous signal generator.
Multiple cameras are fed into the signal from the synchronous signal generator at exactly the same time, and only the frame at the time when the signal is entered is recorded, resulting in perfectly synchronized recording and not being affected by the camera clock or environment.