F-number lengths. Therefore, reduced–depth-of-field effects will require smaller f-numbers when using small-format cameras than when using larger-format cameras. Image sharpness is related to f/number through two different optical effects: aberration, due to imperfect lens design, and diffraction which is due to the wave nature of light. The blur optimal f-stop varies with the lens design. For modern standard lenses having 6 or 7 elements, the sharpest image is often obtained around 5.6–8, while for older standard lenses having only 4 elements (Tessar formula) stopping to 11 will give the sharpest image. The larger number of elements in modern lenses allow the
Adler Standard 6 over from the 6N. The rebodied Standard 6 (3U) appeared at the Berlin Motor Show in February 1933. The 2,916cc side-valve six cylinder engine was carried forward from the existing Standard 6. The new car had a lower body frame and independent suspension at the front like the smaller engined Adler Favorit which appeared in the same year. Attention also focused on the new ZF four speed transmission and the standard all-steel body which, as before, came from Ambi-Budd in the Spandau district of Berlin. 400 of these cars were built before the model was replaced by the Adler Diplomat