The Rodenstock 120mm f/5.6 Apo-Macro-Sironar digital Lens is a large format lens specifically designed for macro use with digital backs, which require a smaller image circle with extreme resolution, color correction, and maximum performance at a large aperture. Its ideal range of sharpness is based upon reproduction ratios as small as 1:5 and as large as 2:1. The Apo-Macro-Sironar digital is recommended for use with backs having a maximum image area of 72 x 96mm, and captures a view upon such a back similar to that of a 50mm macro lens upon a 35mm format camera.
In many cases, digital photography is superior to conventional photography if the desired end product is a printed image. To achieve this ideal, however, a much higher demand is made upon the image reproduction quality of the lens. This is because of a digital image chip's smaller area, which means finer details in a scene are squeezed into a smaller image recording area, as well as their sensitivity to color fringes.
But Rodenstock's digitally-specific lenses such as this Apo-Macro-Sironar digital provide image quality which allows the maximum capacity of a digital back to be realized. The lens utilizes every technological possibility to get as close as possible to the absolute limits of diffraction-determined resolution, even accounting for the properties and thickness of a CCD's protective glass. With the Apo-Macro-Sironar digital, you can use digital backs with a pixel pitch as small as 5µ.
Despite its exclusive design for the macro realm, the Apo-Macro-Sironar digital is recommended for use at apertures of f/8-11; you should primarily use your camera's movements to control the depth of field. Given its 120mm focal length (which allows plenty of space) and because it benefits from superior optical design without any needed concessions for an SLR camera's mirror box, this lens is commonly adapted for use with DSLR cameras as a product reproduction specialist. It can document items as small as 12x18mm in size, with remarkable resolution that would be impossible to achieve with any SLR system macro lens.