26.7 m
Hyperfocal distance
13.4 m
Sharp from (focused at hyperfocal)
80 mm f/8.0
Full-frame equivalent
30°
Diagonal angle of view
Depth of field by subject distance#
40 mm at f/4 on Micro Four Thirds (17.3×13 mm), circle of confusion 15 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) | 29.7 cm | 30.3 cm | 0.6 cm | 50% / 50% | 8.89% |
| 50.0 cm (1.64 ft) | 49.2 cm | 50.9 cm | 1.7 cm | 49% / 51% | 5.03% |
| 75.0 cm (2.46 ft) | 73.1 cm | 77.1 cm | 4.0 cm | 49% / 51% | 3.26% |
| 1.00 m (3.28 ft) | 96.5 cm | 1.04 m | 7.2 cm | 48% / 52% | 2.41% |
| 1.50 m (4.92 ft) | 1.42 m | 1.59 m | 16.5 cm | 47% / 53% | 1.58% |
| 2.00 m (6.56 ft) | 1.86 m | 2.16 m | 29.6 cm | 46% / 54% | 1.18% |
| 3.00 m (9.84 ft) | 2.70 m | 3.37 m | 67.4 cm | 44% / 56% | 0.78% |
| 4.00 m (13.1 ft) | 3.48 m | 4.70 m | 1.21 m | 43% / 57% | 0.58% |
| 5.00 m (16.4 ft) | 4.22 m | 6.14 m | 1.93 m | 41% / 59% | 0.47% |
| 7.00 m (23.0 ft) | 5.55 m | 9.47 m | 3.92 m | 37% / 63% | 0.33% |
| 10.0 m (32.8 ft) | 7.28 m | 16.0 m | 8.68 m | 31% / 69% | 0.23% |
| 15.0 m (49.2 ft) | 9.61 m | 34.2 m | 24.6 m | 22% / 78% | 0.15% |
| 20.0 m (65.6 ft) | 11.4 m | 79.5 m | 68.1 m | 13% / 87% | 0.12% |
| 30.0 m (98.4 ft) | 14.1 m | ∞ | ∞ | — | 0.08% |
| 50.0 m (164 ft) | 17.4 m | ∞ | ∞ | — | 0.05% |
| 100 m (328 ft) | 21.1 m | ∞ | ∞ | — | 0.02% |
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/4#
| Focal length | Subject at | Total DoF |
|---|---|---|
| 14 mm | 3.00 m | 33.3 m |
| 16 mm | 3.00 m | 8.21 m |
| 20 mm | 3.00 m | 3.35 m |
| 24 mm | 3.00 m | 2.06 m |
| 28 mm | 3.00 m | 1.44 m |
| 35 mm | 3.00 m | 89.0 cm |
| 40 mm | 3.00 m | 67.4 cm |
| 50 mm | 3.00 m | 42.7 cm |
| 85 mm | 3.00 m | 14.5 cm |
| 105 mm | 3.00 m | 9.5 cm |
| 135 mm | 3.00 m | 5.7 cm |
| 200 mm | 10.0 m | 29.4 cm |
| 300 mm | 10.0 m | 12.9 cm |
| 400 mm | 10.0 m | 7.2 cm |
| 600 mm | 10.0 m | 3.1 cm |
Same lens settings on other formats#
When to use it#
At f/4, a 40 mm lens on Micro Four Thirds is a natural choice for general photography. Focused at 3 m you get 67.4 cm of sharp zone; for maximum front-to-back sharpness focus at 26.7 m and everything from 13.4 m to infinity will be acceptably sharp.
See also the f/4 aperture guide.
Frequently asked questions#
What is the depth of field of a 40mm lens at f/4?
On Micro Four Thirds, focused at 3 m, it is 67.4 cm; at 1 m it is 7.2 cm.
What is the hyperfocal distance for 40mm f/4?
26.7 m (87.6 ft) on Micro Four Thirds. Everything from 13.4 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources