Four Types of Lens Units:
The Horseman SW-D Pro lens units come quipped with German Schneider and Rodenstock digital lenses. The shortest focal length, the Schneider Apo-Digitar XL24, is one of four available lens units that include Rodenstock Apo-Sironar digital lenses of 35, 45 and 55mm focal lengths. What's more, Horseman SW series(originally for film cameras) lenses can also be used.
What Is A 'Digital Lens' ?
Digital photography, as opposed to conventional film or "chemical' processes, makes its own demands on the camera lens. A lens optimized for digital should fulfill these conditions:
• 1. The image circle can be smaller, but inside that circle optical resolution and contrast should be as high as possible.
• 2. In conventional large format cameras, optical resolution was considered good if it resulted in about 20 lines per millimeter. In view of the high resolution of today's digital sensors, lens resolution should be several times higher, up to 100 lines per mm.
• 3. Resolution of the digital image drops visibly at stopped-down apertures (f-stops). For digital photography, a lens should be designed to provide optimumMTF at relatively wide apertures.
The Horseman Original Helicoid Mount
The helicoid mount used in the SW-D lens units is a new and original Horseman development designed for highest possible precision. Each model is equipped witha distance scale and a depth-of-field scale for the lens it is used on.
|Lens||SW-D 45mm Lens Unit: Apo-Sironar 45mm F/4.5|
|Image circle||125mm Diag.|
|Vertical Shift||max 34mm (17mm Rise/Fall each)*|
|Lateral Shift||max 30mm (15mm L/R each)*|
|Closest Focusing Distance||0.4m|