38.1 m
Hyperfocal distance
19.1 m
Sharp from (focused at hyperfocal)
40 mm f/1.4
Full-frame equivalent
57°
Diagonal angle of view
Depth of field by subject distance#
40 mm at f/1.4 on full frame (36×24 mm), circle of confusion 30 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) | 29.8 cm | 30.2 cm | 0.4 cm | 50% / 50% | 12.21% |
| 50.0 cm (1.64 ft) | 49.4 cm | 50.6 cm | 1.2 cm | 49% / 51% | 6.90% |
| 75.0 cm (2.46 ft) | 73.6 cm | 76.4 cm | 2.8 cm | 49% / 51% | 4.47% |
| 1.00 m (3.28 ft) | 97.5 cm | 1.03 m | 5.0 cm | 49% / 51% | 3.31% |
| 1.50 m (4.92 ft) | 1.44 m | 1.56 m | 11.5 cm | 48% / 52% | 2.17% |
| 2.00 m (6.56 ft) | 1.90 m | 2.11 m | 20.6 cm | 47% / 53% | 1.62% |
| 3.00 m (9.84 ft) | 2.78 m | 3.25 m | 46.9 cm | 46% / 54% | 1.07% |
| 4.00 m (13.1 ft) | 3.62 m | 4.46 m | 84.1 cm | 45% / 55% | 0.80% |
| 5.00 m (16.4 ft) | 4.42 m | 5.75 m | 1.32 m | 43% / 57% | 0.64% |
| 7.00 m (23.0 ft) | 5.92 m | 8.56 m | 2.65 m | 41% / 59% | 0.46% |
| 10.0 m (32.8 ft) | 7.93 m | 13.5 m | 5.61 m | 37% / 63% | 0.32% |
| 15.0 m (49.2 ft) | 10.8 m | 24.7 m | 13.9 m | 30% / 70% | 0.21% |
| 20.0 m (65.6 ft) | 13.1 m | 42.0 m | 28.9 m | 24% / 76% | 0.16% |
| 30.0 m (98.4 ft) | 16.8 m | 140 m | 124 m | 11% / 89% | 0.11% |
| 50.0 m (164 ft) | 21.6 m | ∞ | ∞ | — | 0.06% |
| 100 m (328 ft) | 27.6 m | ∞ | ∞ | — | 0.03% |
Try other settings#
Near limit—
Far limit—
Depth of field—
Hyperfocal distance—
In front / behind—
40 mm at other apertures (subject at 3 m)#
Other focal lengths at f/1.4#
Same lens settings on other formats#
When to use it#
At f/1.4, a 40 mm lens on full frame is a natural choice for environmental portraits, street and low light. Focused at 3 m you get 46.9 cm of sharp zone; for maximum front-to-back sharpness focus at 38.1 m and everything from 19.1 m to infinity will be acceptably sharp.
See also the f/1.4 aperture guide.
Frequently asked questions#
What is the depth of field of a 40mm lens at f/1.4?
On full frame, focused at 3 m, it is 46.9 cm; at 1 m it is 5.0 cm.
What is the hyperfocal distance for 40mm f/1.4?
38.1 m (125 ft) on full frame. Everything from 19.1 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources