An inverted telephoto lens is a specialized lens design that provides a short focal length while maintaining a long back focus. This construction allows for additional space behind the lens, accommodating mirrors, shutters, and other camera components, making it ideal for small-format cameras.
Understanding inverted telephoto lenses is particularly useful for photographers using wide-angle lenses on SLR or mirrorless cameras, where internal camera mechanisms require extra clearance. These lenses are commonly used in landscape, architectural, and cinematic photography, offering wide fields of view without interfering with the camera's internal components.