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 interest among the chattering classes. Gropius developed a completely new body for the Adler Standard which was exhibited at the Paris Motor Show in October 1930 and a few months later at the Berlin show. The cars attracted much attention and comment, but very few serious customers. As far as is known 3 of the Gropius designed Adler Standard saloons were built by coachbuilders Neuss and a further 3 cabriolets were built by coachbuilders Karmann. The Gropius venture into car design is accordingly historically interesting but not commercially significant. The exercise had its parallel in France where at about the