66.7 m
Hyperfocal distance
33.4 m
Sharp from (focused at hyperfocal)
61 mm f/1.8
Full-frame equivalent
39°
Diagonal angle of view
Depth of field by subject distance#
40 mm at f/1.2 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) | 29.9 cm | 30.1 cm | 0.2 cm | 50% / 50% | 21.82% |
| 50.0 cm (1.64 ft) | 49.7 cm | 50.3 cm | 0.7 cm | 50% / 50% | 12.33% |
| 75.0 cm (2.46 ft) | 74.2 cm | 75.8 cm | 1.6 cm | 49% / 51% | 7.99% |
| 1.00 m (3.28 ft) | 98.6 cm | 1.01 m | 2.9 cm | 49% / 51% | 5.91% |
| 1.50 m (4.92 ft) | 1.47 m | 1.53 m | 6.6 cm | 49% / 51% | 3.89% |
| 2.00 m (6.56 ft) | 1.94 m | 2.06 m | 11.8 cm | 49% / 51% | 2.89% |
| 3.00 m (9.84 ft) | 2.87 m | 3.14 m | 26.7 cm | 48% / 52% | 1.92% |
| 4.00 m (13.1 ft) | 3.78 m | 4.25 m | 47.7 cm | 47% / 53% | 1.43% |
| 5.00 m (16.4 ft) | 4.65 m | 5.40 m | 74.8 cm | 46% / 54% | 1.14% |
| 7.00 m (23.0 ft) | 6.34 m | 7.82 m | 1.48 m | 45% / 55% | 0.82% |
| 10.0 m (32.8 ft) | 8.70 m | 11.8 m | 3.06 m | 43% / 57% | 0.57% |
| 15.0 m (49.2 ft) | 12.3 m | 19.3 m | 7.09 m | 39% / 61% | 0.38% |
| 20.0 m (65.6 ft) | 15.4 m | 28.5 m | 13.2 m | 35% / 65% | 0.28% |
| 30.0 m (98.4 ft) | 20.7 m | 54.5 m | 33.8 m | 28% / 72% | 0.19% |
| 50.0 m (164 ft) | 28.6 m | 200 m | 171 m | 13% / 87% | 0.11% |
| 100 m (328 ft) | 40.0 m | ∞ | ∞ | — | 0.06% |
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/1.2#
Same lens settings on other formats#
When to use it#
At f/1.2, a 40 mm lens on APS-C is a natural choice for environmental portraits, street and low light. Focused at 3 m you get 26.7 cm of sharp zone; for maximum front-to-back sharpness focus at 66.7 m and everything from 33.4 m to infinity will be acceptably sharp.
See also the f/1.2 aperture guide.
Frequently asked questions#
What is the depth of field of a 40mm lens at f/1.2?
On APS-C, focused at 3 m, it is 26.7 cm; at 1 m it is 2.9 cm.
What is the hyperfocal distance for 40mm f/1.2?
66.7 m (219 ft) on APS-C. Everything from 33.4 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources