Ultra-wideS: wraparound and full imm

You’ll get a visually extreme effect from an ultra-wide, and that calls for careful composition

One of the results of increasingly sophisticated lens design is better performance at the extremes of focal length. A side effect of this is that the distinction between ‘normal’ wide-angle and ultra-wide has shifted over the years, and most photographers now consider 20mm to be ultra-wide.

The defining quality of an ultra-wide lens is a view wider than most people would be aware of without turning their head from side to side. This is one of two ways in which ultra-wide is visually extreme – an angle of view greater than we experience. The second extreme effect is the inevitable distortion, which can be somewhere between powerful and weird, depending on your taste. One of the lens designer’s main tasks with an ultra-wide is to correct barrel distortion, in which straight lines close to and parallel to the frame edges bend outwards, like on a barrel. Achieving this, however,