APO-MACRO-SUMMARIT-S 120 f/2.5 (CS)
The perfect portrait lens
Much more than just a portrait lens
The APO-Macro-Summarit-S 120 f/2.5 (CS) (96 mm in 35 mm format) has a true dual function. Firstly, it is a macro lens for closeup photography up to a reproduction ratio of 1:2, and secondly, it is a fast telephoto lens with an unusually wide maximum aperture of f/2.5.
At the same time, it offers such astounding imaging qualities at maximum aperture throughout its entire focusing range that stopping down really only increases the depth of field but cannot further increase its superior contrast rendition. This brings countless fascinating options for exploring the creative opportunities offered by selective sharpness. The alternative CS version with a central shutter further increases its enormous range of potential uses.
The highlights
From close-up to telephoto photography
From close-ups to tele-photography
Real double benefit: On the one hand it is a macro lens for close-up images up to 1:2 scale, on the other hand it is a fast telephoto lens.
Innovative central shutter for maximum design freedom when using additional light
Excellent imaging performance over the entire range and at all aperture settings
Extremely fast
Creative use of sharpness and blurring for the plastic extraction of motif details
Best image quality up to the edges due to aspherical optics
Weather- and dust-sealed lens
Technical Details
The lens design comprises nine elements in seven groups, and its frontgroup focusing with a floating element guarantees outstanding contrast performance at even the shortest focusing distances of the macro domain. Three elements are made of glasses with anomalous partial dispersion and two of these have extremely low dispersion, which minimizes monochromatic aberrations.
The sophisticated apochromatic correction enables perfect resolution of even high-contrast finedetail structures.
Modulation Transfer Function
The MTF is indicated both at full aperture and at f/5.6 and f/8 at long taking distances (infinity).
Shown is the contrast in percentage for 5, 10, 20 and 40 lp/mm across the height of the 35mm film format, for tangential (dotted line) and sagittal (solid line) structures, in white light. The 5 and 10 lp/mm will give an indication regarding the contrast ratio for large object structures. The 20 and 40 lp/mm records the resolution of finer and finest object structures.
Distortion & vignetting
Distortion is the deviation of the real image height (in the picture) from the ideal image height. The relative distortion is the percentage deviation. The ideal image height results from the object height and the magnification. The image height of 27.04mm is the radial distance between the edge and the middle of the image field for the format 30mm×45mm.
