Camera Lenses Quiz

Camera Lenses: An Overview

• A camera lens is an optical lens or assembly of lenses used with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.

• The details of design and construction are different for lenses used for a still camera, a video camera, a telescope, a microscope, or other apparatus.

• A compound lens made up of a number of optical lens elements is required to correct the many optical aberrations that arise.

• The front element is critical to the performance of the whole assembly and is usually coated to reduce abrasion, flare, and surface reflectance, and to adjust color balance.

• Glass is the most common material used to construct lens elements, due to its good optical properties and resistance to scratching.

• The widest aperture lens in history of photography is believed to be the Carl Zeiss Planar 50mm f/0.7, which was designed and made specifically for the NASA Apollo lunar program to capture the far side of the moon in 1966.

• The two fundamental parameters of an optical lens are the focal length and the maximum aperture.

• The maximum usable aperture of a lens is specified as the focal ratio or f-number, defined as the lens's focal length divided by the effective aperture.

• For a given photographic system, the focal length determines the angle of view, and the aperture the light intensity of that image.

• Many single-lens reflex cameras and some rangefinder cameras have detachable lenses. The lenses attach to the camera using a lens mount, which contains mechanical linkages and often also electrical contacts between the lens and camera body.

• There is no universal standard for lens mounts, and each major camera maker typically uses its own proprietary design, incompatible with other makers.

• A macro lens used in macro or "close-up" photography is any lens that produces an image on the focal plane that is one quarter of life size (1:4) to the same size (1:1) as the subject being imaged.Overview of Photographic Lens Types and Designs

• Photographic lenses are optical devices that refract light in order to form an image on a light-sensitive surface.

• Prime lenses have a fixed focal length, which means that they cannot zoom in or out.

• Zoom lenses have a variable focal length, which means that they can zoom in or out.

• Zoom lenses are widely used for small-format cameras of all types, including still and cine cameras with fixed or interchangeable lenses.

• Motorized zoom lenses may have the focus, iris, and other functions motorized.

• Special-purpose lenses, such as fisheye, tilt-shift, and macro lenses, are designed for specific photographic applications.

• The history of photographic lenses dates back to the early 19th century, with the development of the first camera obscura.

• Technical developments in lens design include the use of new materials, coatings, and manufacturing techniques.

• Some notable photographic optical lens designs include the Cooke triplet, the Tessar, and the Planar.

• The performance of a photographic lens is typically evaluated based on factors such as sharpness, contrast, distortion, and bokeh.

• The choice of lens depends on the photographer's artistic vision, subject matter, and shooting conditions.

• The use of interchangeable lenses allows photographers to choose the best lens for each situation, and to achieve a wide range of creative effects.