Why should the camera add ND when shooting, and don't speed up the door opening?

My understanding is that accelerating the door opening without using lights outside the sun will affect the dynamic blur. When the number of frames is constant, the shutter is too high, which will make each frame clear (just like raising the shutter to capture a clear picture of a moving object in photo photography). The human eye is used to dynamic blurred frames, whether it is 24 or 25 frames. If the shutter is too high, the shot picture will lose or reduce the blurred picture in the middle, which makes people uncomfortable at first sight. Low shutter will increase the blurred frame in the middle, and the dynamic picture will form smear. You can occasionally reduce the shutter and increase the aperture in a picture with little dynamic. In the case of using ballast lamps, it is necessary to match the domestic current frequency of 50HZ (the current frequency of the United States and Japan 1 10V is 60HZ), and the shutter is also (24 grids 172.8 degrees, and 25 grids 180 degrees is equivalent to1/50s). I think it is possible to add and subtract the shutter within a certain period of time (I often use 180 degrees and 90 degrees when shooting 25 frames with BMCC, and occasionally use 45 degrees). As for adding ND, there is nothing I can do. From the optical principle (excluding some lenses that have to be added to correct distortion and aberration), the fewer lenses in the lens, the better, so adding more glass in front of the lens will definitely affect the imaging. So I think adding ND is the way we have to go, because speeding up the door opening will affect the dynamic blur of the picture and achieve an important depth of field! (The above is my personal opinion, and I hope other great gods can correct me. ) See more answers >>