7.16 m
Hyperfocal distance
3.58 m
Sharp from (focused at hyperfocal)
31 mm f/4.3
Full-frame equivalent
70°
Diagonal angle of view
Depth of field by subject distance#
20 mm at f/2.8 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) | 28.9 cm | 31.2 cm | 2.4 cm | 48% / 52% | 2.17% |
| 50.0 cm (1.64 ft) | 46.9 cm | 53.6 cm | 6.8 cm | 47% / 53% | 1.27% |
| 75.0 cm (2.46 ft) | 68.0 cm | 83.5 cm | 15.5 cm | 45% / 55% | 0.83% |
| 1.00 m (3.28 ft) | 87.9 cm | 1.16 m | 28.0 cm | 43% / 57% | 0.62% |
| 1.50 m (4.92 ft) | 1.24 m | 1.89 m | 64.9 cm | 40% / 60% | 0.41% |
| 2.00 m (6.56 ft) | 1.57 m | 2.77 m | 1.20 m | 36% / 64% | 0.31% |
| 3.00 m (9.84 ft) | 2.12 m | 5.15 m | 3.03 m | 29% / 71% | 0.20% |
| 4.00 m (13.1 ft) | 2.57 m | 9.03 m | 6.46 m | 22% / 78% | 0.15% |
| 5.00 m (16.4 ft) | 2.95 m | 16.5 m | 13.6 m | 15% / 85% | 0.12% |
| 7.00 m (23.0 ft) | 3.54 m | 307 m | 303 m | 1% / 99% | 0.09% |
| 10.0 m (32.8 ft) | 4.17 m | ∞ | ∞ | — | 0.06% |
| 15.0 m (49.2 ft) | 4.84 m | ∞ | ∞ | — | 0.04% |
| 20.0 m (65.6 ft) | 5.27 m | ∞ | ∞ | — | 0.03% |
| 30.0 m (98.4 ft) | 5.77 m | ∞ | ∞ | — | 0.02% |
| 50.0 m (164 ft) | 6.25 m | ∞ | ∞ | — | 0.01% |
| 100 m (328 ft) | 6.67 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/2.8#
Same lens settings on other formats#
When to use it#
At f/2.8, a 20 mm lens on APS-C is a natural choice for environmental portraits, street and low light. Focused at 3 m you get 3.03 m of sharp zone; for maximum front-to-back sharpness focus at 7.16 m and everything from 3.58 m to infinity will be acceptably sharp.
See also the f/2.8 aperture guide.
Frequently asked questions#
What is the depth of field of a 20mm lens at f/2.8?
On APS-C, focused at 3 m, it is 3.03 m; at 1 m it is 28.0 cm.
What is the hyperfocal distance for 20mm f/2.8?
7.16 m (23.5 ft) on APS-C. Everything from 3.58 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources