The 6 elements design guarantees the resolution of the finest details while maintaining a uniformly high contrast from the picture center to the edges. As the lens is nearly independent with regard to magnification scale, top quality is ensured from mini-prints right up to high enlargements. The recommended working aperture is reached by stopping down by only 2 stops from open aperture. This Rodagon lens is equipped with an illuminated f-stop display, a practical pre-set aperture und a click-stop diaphragm which can be switched to stepless control . Maximum film format: 6x7cmFocal length: 80mmScale range: 2-10xSmallest aperture: f/22Largest aperture: f/4.0Filter thread: M 40.5x0.5Screw thread: M39