Angle of view camera–subject distance to preserve the size of a subject, changing the angle of view can indirectly distort perspective, changing the apparent relative size of the subject and foreground. If the subject image size remains the same, then at any given aperture all lenses, wide angle and long lenses, will give the same depth of field. An example of how lens choice affects angle of view. This table shows the diagonal, horizontal, and vertical angles of view, in degrees, for lenses producing rectilinear images, when used with 36 mm × 24 mm format (that is, 135 film or full-frame 35mm digital
Angle of parallelism Angle of parallelism In hyperbolic geometry, the angle of parallelism formula_1, is the angle at one vertex of a right hyperbolic triangle that has two asymptotic parallel sides. The angle depends on the segment length "a" between the right angle and the vertex of the angle of parallelism. Given a point off of a line, if we drop a perpendicular to the line from the point, then "a" is the distance along this perpendicular segment, and "φ" or formula_1 is the least angle such that the line drawn through the point at that angle does not intersect the given line.