Panoramic photography widest field of view that can be captured in focus and without significant wide-angle distortion or vignetting. Lenses with an imaging angle approaching 120 degrees require a center filter to correct vignetting at the edges of the image. Lenses that capture angles of up to 180°, commonly known as fisheye lenses exhibit extreme geometrical distortion but typically display less brightness falloff than rectilinear lenses. Examples of this type of camera are: Sicialian Camera Works Pannaroma (35mm, 1987), Hasselblad X-Pan (35 mm, 1998), Linhof 612PC, Horseman SW612, Linhof Technorama 617, Tomiyama Art Panorama 617 and 624, and Fuji G617 and GX617
Degrees of freedom (mechanics) in which a phased array antenna can form either beams or nulls. It is equal to one less than the number of elements contained in the array, as one element is used as a reference against which either constructive or destructive interference may be applied using each of the remaining antenna elements. Radar practice and communication link practice, with beam steering being more prevalent for radar applications and null steering being more prevalent for interference suppression in communication links. Degrees of freedom (mechanics) In physics, the degree of freedom (DOF) of a mechanical system is the number of independent parameters