10.0 m
Hyperfocal distance
5.01 m
Sharp from (focused at hyperfocal)
31 mm f/3.1
Full-frame equivalent
70°
Diagonal angle of view
Depth of field by subject distance#
20 mm at f/2 on APS-C (23.5×15.6 mm), circle of confusion 20 µm. “Background blur” is the size of an out-of-focus light at infinity as a percentage of frame width.
| Focus distance | Near limit | Far limit | Total DoF | Front / behind | Background blur |
|---|---|---|---|---|---|
| 30.0 cm (0.98 ft) | 29.2 cm | 30.9 cm | 1.7 cm | 49% / 51% | 3.04% |
| 50.0 cm (1.64 ft) | 47.7 cm | 52.5 cm | 4.8 cm | 48% / 52% | 1.77% |
| 75.0 cm (2.46 ft) | 69.9 cm | 80.9 cm | 11.0 cm | 46% / 54% | 1.17% |
| 1.00 m (3.28 ft) | 91.1 cm | 1.11 m | 19.8 cm | 45% / 55% | 0.87% |
| 1.50 m (4.92 ft) | 1.31 m | 1.76 m | 45.4 cm | 43% / 57% | 0.58% |
| 2.00 m (6.56 ft) | 1.67 m | 2.49 m | 82.4 cm | 40% / 60% | 0.43% |
| 3.00 m (9.84 ft) | 2.31 m | 4.27 m | 1.96 m | 35% / 65% | 0.29% |
| 4.00 m (13.1 ft) | 2.86 m | 6.64 m | 3.78 m | 30% / 70% | 0.21% |
| 5.00 m (16.4 ft) | 3.34 m | 9.96 m | 6.62 m | 25% / 75% | 0.17% |
| 7.00 m (23.0 ft) | 4.12 m | 23.2 m | 19.1 m | 15% / 85% | 0.12% |
| 10.0 m (32.8 ft) | 5.01 m | 5.0 km | 5.0 km | 0% / 100% | 0.09% |
| 15.0 m (49.2 ft) | 6.00 m | ∞ | ∞ | — | 0.06% |
| 20.0 m (65.6 ft) | 6.67 m | ∞ | ∞ | — | 0.04% |
| 30.0 m (98.4 ft) | 7.50 m | ∞ | ∞ | — | 0.03% |
| 50.0 m (164 ft) | 8.34 m | ∞ | ∞ | — | 0.02% |
| 100 m (328 ft) | 9.09 m | ∞ | ∞ | — | 0.01% |
Try other settings#
Near limit—
Far limit—
Depth of field—
Hyperfocal distance—
In front / behind—
20 mm at other apertures (subject at 3 m)#
Other focal lengths at f/2#
Same lens settings on other formats#
When to use it#
At f/2, a 20 mm lens on APS-C is a natural choice for environmental portraits, street and low light. Focused at 3 m you get 1.96 m of sharp zone; for maximum front-to-back sharpness focus at 10.0 m and everything from 5.01 m to infinity will be acceptably sharp.
See also the f/2 aperture guide.
Frequently asked questions#
What is the depth of field of a 20mm lens at f/2?
On APS-C, focused at 3 m, it is 1.96 m; at 1 m it is 19.8 cm.
What is the hyperfocal distance for 20mm f/2?
10.0 m (32.9 ft) on APS-C. Everything from 5.01 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources