2.7 km
Hyperfocal distance
1.3 km
Sharp from (focused at hyperfocal)
800 mm f/8.0
Full-frame equivalent
3°
Diagonal angle of view
Depth of field by subject distance#
400 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 |
|---|---|---|---|---|---|
| 1.00 m (3.28 ft) | 100.0 cm | 1.00 m | 0.0 cm | 50% / 50% | 385.36% |
| 1.50 m (4.92 ft) | 1.50 m | 1.50 m | 0.1 cm | 50% / 50% | 210.19% |
| 2.00 m (6.56 ft) | 2.00 m | 2.00 m | 0.2 cm | 50% / 50% | 144.51% |
| 3.00 m (9.84 ft) | 3.00 m | 3.00 m | 0.6 cm | 50% / 50% | 88.93% |
| 4.00 m (13.1 ft) | 3.99 m | 4.01 m | 1.1 cm | 50% / 50% | 64.23% |
| 5.00 m (16.4 ft) | 4.99 m | 5.01 m | 1.7 cm | 50% / 50% | 50.26% |
| 7.00 m (23.0 ft) | 6.98 m | 7.02 m | 3.5 cm | 50% / 50% | 35.03% |
| 10.0 m (32.8 ft) | 9.96 m | 10.0 m | 7.2 cm | 50% / 50% | 24.08% |
| 15.0 m (49.2 ft) | 14.9 m | 15.1 m | 16.4 cm | 50% / 50% | 15.84% |
| 20.0 m (65.6 ft) | 19.9 m | 20.1 m | 29.4 cm | 50% / 50% | 11.80% |
| 30.0 m (98.4 ft) | 29.7 m | 30.3 m | 66.6 cm | 49% / 51% | 7.81% |
| 50.0 m (164 ft) | 49.1 m | 50.9 m | 1.86 m | 49% / 51% | 4.66% |
| 100 m (328 ft) | 96.4 m | 104 m | 7.48 m | 48% / 52% | 2.32% |
Try other settings#
Near limit—
Far limit—
Depth of field—
Hyperfocal distance—
In front / behind—
400 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 400 mm lens on Micro Four Thirds is a natural choice for general photography. Focused at 3 m you get 0.6 cm of sharp zone; for maximum front-to-back sharpness focus at 2.7 km and everything from 1.3 km to infinity will be acceptably sharp.
See also the f/4 aperture guide.
Frequently asked questions#
What is the depth of field of a 400mm lens at f/4?
On Micro Four Thirds, focused at 3 m, it is 0.6 cm; at 1 m it is 0.0 cm.
What is the hyperfocal distance for 400mm f/4?
2.7 km (8750 ft) on Micro Four Thirds. Everything from 1.3 km to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources