There is a picture of a black car, why does the car look black?

Because its black....
That's a confusing question! Comment what you mean ;)

Because the camera that took the picture set the pixels for that area of the photo to black if it was a digital camera or the film responded to the area of the car as black if it was that type camera. Cameras don't always render the color in the picture to the exact color as the object depending on the light source.

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