What it frames
The Fujifilm X-T30 III with the Tamron 17-70mm f/2.8 Di III-A VC RXD, 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 APS-C sensor (23.5 x 15.6 mm) has a crop factor of 1.5, so the dashed frames are marked with the focal length that gives the same view on it.
17mm on the Fujifilm X-T30 III frames 6.91 m × 4.59 m at 5 m: like 26mm on full frame, 69° across.
The numbers
- Frame at 5 m6.91 m × 4.59 m
- Full-frame equivalent26mm
- Angle of view69° × 49°, 79° diagonal
- Depth of field at f/2.82.62 m to 54.3 m (51.6 m)
- Depth of field at f/81.39 m to infinity (to infinity)
- Hyperfocal at f/2.85.51 m
- Hyperfocal at f/81.94 m
- Circle of confusion0.019 mm
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.