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
School Number 6 (Davenport, Iowa) Taylor School in Davenport. The former Jackson School building was listed on the Davenport Register of Historic Properties and on the National Register of Historic Places in 2011. School Number 6 (Davenport, Iowa) School Number 6 is an historic building located in Davenport, Iowa, United States. The building was completed in 1903. It was later renamed Jackson School and served the public school district into the 1940s. From 1943 to 1964 the building served as a parochial school for Holy Family Catholic Church. Since then it has been an office building. In 2010 the building was purchased by Renaissance Realty