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SS - Shutter Speed can be described either as an angle (shutter angle), or as a length of time in seconds (exposure time). Everyone here is talking about shutter ANGLEs, not exposure times (in seconds). You are referring to shutter speed described at exposure time in seconds. As a videographer, you can not confuse these to terms. So what is the difference between those two? Well, shutter speed as expressed by exposure time is easy. Its just the time the camera lets light into the sensor (thats an oversimplificaiton, but you get the point). For example, with 1/50s shutter speed, the sensor gathers light for 20 milliseconds (or 1/50 of a second). Easy. but with shutter angle its not that easy, beacuse shutter angle is also tied to framerate. If youre recording in 30 FPS for example, then you might have been told to use the "180 degree rule" and double the frame rate to get the inversion of the value you should set you exposure time to. Which would be 1/60s (because 30*2=60) But why is 1/60s of exposure time equal to 180 degrees of shutter angle? Imagine a circle. And inside that circle is an angle. If that angle is equal to 360 degrees, the circle if full. full of what? Full of light. If the angle equals to 180 degrees, the circle is half-full. 90 degrees - quarter full, etc. Your angle can not be fuller than 360 degrees. So if you have your framerate of 30 FPS, then one frame takes aobut 33.3 milliseconds. That is also the maximum time duration you can let light through into the sensor. If you want more time, you have to decrease the framerate. So when shooting at 30 FPS you cannot have shutter speed greater than 360 degrees or 1/30 of a second (33.3 milliseconds). Cinematic film is in 24 FPS, so the longest exposure time you can get is 1/24 of a second or again, 360 degrees. Do you see why we use both exposure times and shutter angles? Shutter angles are not related to framerate, where as shutter speed is. So your camera - the a7iii CAN shoot with a 360 shutter angle. You just have to set your shutter speed accordingly. For 24 FPS thats 1/24s, for 25 FPS thats 1/25s, for 30 FPS thats 1/30s, for 60 FPS thats 1/60s. All these pairs of values represent a 360 shutter angle. So you might ask yourself why can you go as low as 1/4s with your sony a7iii? Watch the framerate closely, as you lenghten your exposure time. The more you get closer to 1/4s the more frames you lose. At 1/4s youre essentially recording at 4 FPS!! And you can see that with naked eye. Why is that? Because the shutter angle can not be larger than 360 degrees! at 4 FPS the equvalent of a 360 shutter angle is 1/4 of a second shutter speed. I hope you understand now the difference between shutter angle and exposure time.