What is the role of "unconventional exposure" in photography? Why are "unconventional exposures" often used in artistic creation?

Example 1: If you want to take a silhouette, you can’t do it with conventional exposure. Conventional exposure is to capture the person clearly, while silhouette is to capture the person dark. The difference between the two is that conventional exposure is metering on the face. , the silhouette is metered by the sky.

Example 2: Use a slow shutter and long exposure to record the trajectory of moving car lights at night, and a regular exposure to freeze the frame.

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