The Horseman 55mm f/4.5 Apo-Grandagon Lens is a Rodenstock 55mm f/4.5 Apo-Grandagon with a standard Copal #0 shutter, but built into a Horseman-specific helical focusing mount and barrel assembly made to fit upon their SW612/SW612 Professional medium format cameras. Used with a 6x12 film back, this lens produces a 91° x 53° field of view, and upon the 612 cameras the helicoid focusing mount allows a minimum focusing distance of 2' (0.6m). Generous amounts of shift are also permitted (only on the 612 Professional).
The 55mm f/4.5 Apo-Grandagon incorporates ED (Extra-low Dispersion) glass, to make truly apochromatic resolution from a wide angle lens possible for the first time. Its large maximum aperture of f/4.5 makes adjustments easier on the ground glass, and the f/11-16 working aperture allows shorter exposure times in outdoor work. The use of the optional #29225 center filter (HOCF67P2.5) is recommended for critical work, especially with transparencies.
|Optical Construction||8 elements in 4 groups|
|Covering Power||110 degrees|
|Image Circle @ Infinity||163mm diameter|
|Shutter Speed||1-1/500 sec., T, B|
|Slip-on Cap Sizes||70mm front, 60mm rear|
|Minimum Focus Distance||2.0' (0.6m)|
|Weight||1.05 lbs (570g)|