ABSTRACT
A number of severe problems are encountered in the design of wide-angle lenses with large apertures. This chapter shows that fisheye lenses are not extensions of wide-angle lenses, but rather a different optical concept. The full 180° hemisphere can be imaged, and with available software the image can be converted to the rectilinear form if desired. If it is difficult to eliminate barrel distortion in a wide-angle lens, leave it in and correct the result with software. This and other in-camera corrections can be found in some modern digital cameras. But this is just the beginning, because the field of view can be extended to spherical panoramas by image stitching. At the time of this writing, cameras are available that produce high-resolution 3D spherical video. This is possible through the simultaneous operation of multiple wide-angle cameras in one enclosure or frame.
