Those of us who don’t lug view cameras around get perspective distortion in our subjects whenever we point the camera up or down (even slightly) or diagonally towards a flat surface. A typical example is the vertical lines of a building leaning in toward the top. Most such images, whether architectural or nature subjects, to look better with the distortion removed, which is why view cameras have been used for serious photography. The front element holding the lens could be tilted and shifted up, down or sideways to correct perspective and alter the plane of focus.
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