What it frames

The Sony RX100 III with its built-in 8.8-26mm f/1.8-2.8 lens, over a 1.75 m person in a street, with a door, a parked car and buildings. Everything is drawn to scale: the solid frame is what the camera takes in, the dashed ones are 24, 50 and 135mm on full frame from the same spot. Its 1-inch sensor (13.2 x 8.8 mm) has a crop factor of 2.7, so the dashed frames are marked with the focal length that gives the same view on it.

8.8mm on the Sony RX100 III frames 7.5 m × 5 m at 5 m: like 24mm on full frame, 74° across.

50mm eq. (19mm)135mm eq. (50mm)8.8mm · like 24mm on full frame7.5 m × 5 m at 5 m
The subject is 5 m away; things behind it are drawn smaller, as the camera sees them.
Inside the frame: the picture you would get.

The numbers

  • Frame at 5 m7.5 m × 5 m
  • Full-frame equivalent24mm
  • Angle of view74° × 53°, 84° diagonal
  • Depth of field at f/1.82.25 m to infinity (to infinity)
  • Depth of field at f/877 cm to infinity (to infinity)
  • Hyperfocal at f/1.84.08 m
  • Hyperfocal at f/892 cm
  • Circle of confusion0.011 mm
f/1.82.25 m to infinity (everything to infinity)f/877 cm to infinity (everything to infinity)camerasubject, 5 m10 m
Depth of field: what is acceptably sharp, wide open and at f/8, focused on the subject.

How it is worked out

The frame at a distance is distance × sensor size ÷ focal length, across and up; the angle of view is 2 × atan(sensor size ÷ (2 × focal length)). Depth of field uses the thin-lens formulas: the hyperfocal distance H = f² ÷ (N × c) + f, the near limit s(H − f) ÷ (H + s − 2f) and the far limit s(H − f) ÷ (H − s), sharp to infinity from H on, with a circle of confusion c of the sensor diagonal ÷ 1500 and, on a zoom whose aperture changes, the maximum aperture taken linearly between its ends. These are for a rectilinear lens; a fisheye takes in more. Ask for this page with Accept: application/json for the numbers alone.