Jyunte
lvl.4
Flight distance : 2103150 ft
United States
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An ND filter will allow you to reduce your shutter speed. Most Hollywood movies are shot at 24fps, a standard which came into being because at the time, it was mechanically difficult to make movie cameras which could transport film through the camera reliably. 24fps is about as slow as you can go and still mimic what the human eye sees. The human eye is only capable of actually "seeing" for fractions of a second at a time. The rest of the time, the eye is resting and not transmitting data to our brains. Whle the eye is resting, we see a lingering after-image from the previous time the eye captured an image. This is called persistence of vision.
When shooting film at 24fps, we want to expose the frame for about half of the time that the film is stationary in front of the lens. If the subject or camera is moving, there will be some motion blur recorded on the film. Again, this is also what happens when we look at moving objects with the human eye, the image is blurred. With video, the same holds true... We expose the sensor to light for half of the time the sensor is recording a frame. The motion blur looks pleasing to the eye, because it looks natural to us. So, when shooting film or video at 24fps, we use a shutter speed of 1/48th second. Most video cameras don't have a 1/48th second setting, so we use the next closest setting, 1/50th second.
The idea of the ND filter is to reduce the amount of light reaching the film/sensor, so that we can expose the scene correctly when our camera is set to record at 24fps with a shutter speed of 1/50th second.
Some will say that as long as your shutter speed is twice the frame rate, you'll achieve the "cinematic look" because you're following the "180-degree shutter rule". But that's not true. A fast frame rate freezes motion, even when the shutter speed is increased to give a 180-degree shutter. This results in what is often called hyper-real images.... Or images "that look like they were shot on a video camera", which is not "cinematic" at all. If it's the effect you're going for, that's fine, of course.
Images shot at 30fps and 1/60 second look pretty similar to those shot at 24fps and 1/50 second.4K on the Mavic just suffers because the bit rate is not high enough and so data has to be compressed. You're seeing compression artifacts in the video. I'm not sure an ND filter will necessarily help.
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