What it frames

The OM System PEN with the OM System M.Zuiko 150-600mm f/5-6.3 IS, over a 30 cm bird on a 1 m fence post. 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 Micro Four Thirds sensor (17.3 x 13 mm) has a crop factor of 2, so the dashed frames are marked with the focal length that gives the same view on it.

150mm on the OM System PEN frames 1.73 m × 1.3 m at 15 m: like 300mm on full frame, 6.6° across.

24mm eq. (12mm)50mm eq. (25mm)135mm eq. (68mm)150mm · like 300mm on full frame1.73 m × 1.3 m at 15 m
The subject is 15 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 15 m1.73 m × 1.3 m
  • Full-frame equivalent300mm
  • Angle of view6.6° × 5.0°, 8.3° diagonal
  • Depth of field at f/514.3 m to 15.7 m (1.43 m)
  • Depth of field at f/813.9 m to 16.2 m (2.3 m)
  • Hyperfocal at f/5312 m
  • Hyperfocal at f/8195 m
  • Circle of confusion0.014 mm
f/514.3 m to 15.7 m (1.43 m)f/813.9 m to 16.2 m (2.3 m)camerasubject, 15 m30 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.