The area of a scenethat a lens covers or sees. Angle of view is determined by the focal length of thelens. A wide-angle lens (short-focal-length) includes more of the scene-a wider angleof view-than a normal (normal-focal-length) or telephoto (long-focal-length) lens.Currently, the widest view available is 220 degree (achieved by Nikon s Nikkor 6mmF2.8 fisheye lens - 220 degree; while the narrowest is Nikon, 2000mm F11 Reflex Nikkor,only slightly over 1 degree of view. It can also be explained as the extent of theview taken in by a lens. For any particular film size, it varies with the focal lengthof the lens. Usually expressed on the diagonal of the image area. Basically,there are three types of angles which can be measured (based on horizontal, verticaland diagonals of the film frame), the lense must be designed to cover the widestangle in the diagonal direction. Thus, the angle of view is the angle between imaginarylines drawn from the opposite ends of the film plane to the second nodal point ofthe lense. All objects within this angle will be recorded by the lense on the film.mirglossary
Light striking a surface is called incident light. It becomes reflected light when it reflects from the surface. The angle of incidence is the angle at which the incident light strikes the surface, and is measured from a line that is perpendicular to the surface (called the normal ).
Also known as the Field of view, FOV and the Angle of the field of view , it is the extent of the view taken in by a lens. The focal length of a lens, in conjunction with film size or image sensor size, determines the angle of view. Wide-angle lenses have a wider angle of view than do telephoto lenses. A standard or normal lens has an angle of view equal to the diagonal of the digital image sensor or the diagonal of the film, which is generally around 52 or 53 for 35-mm film.
The maximum angle a lens covers in the field. Measured in degrees, and qualified by terms such as wide-angle, normal, and telephoto. A wide angle lens has a wider angle of view than a telephoto lens. A 135mm lens on a 35mm SLR covers an 18-degree angle of view a 28mm lens covers a 75-degree angle of view.
The measurement in degrees of the angle formed by lines projecting from the center of the flash to the extremities of the field of coverage.
The angle of light hitting a surface. A basic rule of physics says that the angle of incidence equals the angle of reflectance, which means that the angle of the light coming towards the surface is the same as the angle of light reflected off of the surface. For example, if light hitting a surface came from a light source that was on a 45 degree angle from the surface, the light reflecting off of the surface would travel on a 45 degree angle as well.