ABSTRACT
Some photographs have a natural appearance, while others seem distorted because nearby objects appear too large or distant objects are flattened. These are natural effects having to do with the perspective point of the image and the tilt of the camera. A normal or natural perspective depends on the angle of view of a photograph relative to that of the original scene. The perspective point of a negative or an image sensor is the center of the camera lens or a distance that is approximately the focal length of the lens. With digital cameras and computer-assisted image processing it is easy to stitch images together to obtain extremely large fields of view. Image processing software such as Photoshop can transform an image to correct for the convergence of lines. Computer programs can correct for lens aberrations and distortions and can even convert images taken with fisheye lenses to rectilinear form.
