How does Panasonic s5 set a constant aperture?

Panasonic s5 sets the constant aperture as follows:

① Changing "SS/ Gain Operation" to ANGEL/ISO in video mode means changing the exposure mode from shutter speed to shutter angle. Generally speaking, when shooting video, the shutter is adjusted to 180 degrees by default (when the shutter angle is 180 degrees, the shutter speed is 1/ twice the frame rate) to obtain the best dynamic blur, and the exposure only needs to pass through ISO and aperture.

② Histogram/vector oscilloscope. I usually shoot videos in vlog mode. At this time, it will be difficult to simply look at the screen exposure, so it is recommended to turn on the histogram to assist the correct exposure. Panasonic's histogram is particularly intuitive. If the histogram is yellow, the machine thinks that the exposure is inaccurate and needs to be adjusted. White is an accurate exposure. Of course, you can also turn on the vector oscilloscope to assist exposure and choose one in a familiar way.

③ Speckle pattern, also used for auxiliary exposure. When the speckle pattern is set to 95%, the best exposure of vlog is that zebra pattern appears in the highlight area on the right, and it is set to 55%-60% when shooting people. When exposing people, when zebra stripes appear in the highlights of the face, it is the best exposure of the face, and it is super easy to use when shooting people.