The reviewer took several shots in sequence to demonstrate the random nature of the auto HDR. I'm just pondering how it happens. The HDR flag not a decision t

The reviewer took several shots in sequence to demonstrate the random nature of the auto HDR. I'm just pondering how it happens. The HDR flag not a decision the software makes at the instant of capture. While composing the shot, there is a liveview from the sensor plus the processing pipeline, including the HDR processing. Does the user not realize/perceive that HDR is enabled before pressing the shutter?