750 m
Hyperfocal distance
375 m
Sharp from (focused at hyperfocal)
300 mm f/4.0
Full-frame equivalent
8°
Diagonal angle of view
Depth of field by subject distance#
300 mm at f/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 |
|---|---|---|---|---|---|
| 75.0 cm (2.46 ft) | 75.0 cm | 75.0 cm | 0.1 cm | 50% / 50% | 138.89% |
| 1.00 m (3.28 ft) | 99.9 cm | 1.00 m | 0.2 cm | 50% / 50% | 89.29% |
| 1.50 m (4.92 ft) | 1.50 m | 1.50 m | 0.5 cm | 50% / 50% | 52.08% |
| 2.00 m (6.56 ft) | 2.00 m | 2.00 m | 0.9 cm | 50% / 50% | 36.76% |
| 3.00 m (9.84 ft) | 2.99 m | 3.01 m | 2.2 cm | 50% / 50% | 23.15% |
| 4.00 m (13.1 ft) | 3.98 m | 4.02 m | 3.9 cm | 50% / 50% | 16.89% |
| 5.00 m (16.4 ft) | 4.97 m | 5.03 m | 6.3 cm | 50% / 50% | 13.30% |
| 7.00 m (23.0 ft) | 6.94 m | 7.06 m | 12.5 cm | 50% / 50% | 9.33% |
| 10.0 m (32.8 ft) | 9.87 m | 10.1 m | 25.9 cm | 49% / 51% | 6.44% |
| 15.0 m (49.2 ft) | 14.7 m | 15.3 m | 58.8 cm | 49% / 51% | 4.25% |
| 20.0 m (65.6 ft) | 19.5 m | 20.5 m | 1.05 m | 49% / 51% | 3.17% |
| 30.0 m (98.4 ft) | 28.9 m | 31.2 m | 2.38 m | 48% / 52% | 2.10% |
| 50.0 m (164 ft) | 46.9 m | 53.5 m | 6.66 m | 47% / 53% | 1.26% |
| 100 m (328 ft) | 88.3 m | 115 m | 27.1 m | 43% / 57% | 0.63% |
Try other settings#
Near limit—
Far limit—
Depth of field—
Hyperfocal distance—
In front / behind—
300 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 | ∞ |
| 16 mm | 3.00 m | ∞ |
| 20 mm | 3.00 m | 26.7 m |
| 24 mm | 3.00 m | 6.04 m |
| 28 mm | 3.00 m | 3.44 m |
| 35 mm | 3.00 m | 1.90 m |
| 40 mm | 3.00 m | 1.40 m |
| 50 mm | 3.00 m | 86.7 cm |
| 85 mm | 3.00 m | 29.1 cm |
| 105 mm | 3.00 m | 18.9 cm |
| 135 mm | 3.00 m | 11.3 cm |
| 200 mm | 10.0 m | 58.9 cm |
| 300 mm | 10.0 m | 25.9 cm |
| 400 mm | 10.0 m | 14.4 cm |
| 600 mm | 10.0 m | 6.3 cm |
Same lens settings on other formats#
When to use it#
At f/4, a 300 mm lens on full frame is a natural choice for general photography. Focused at 3 m you get 2.2 cm of sharp zone; for maximum front-to-back sharpness focus at 750 m and everything from 375 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 300mm lens at f/4?
On full frame, focused at 3 m, it is 2.2 cm; at 1 m it is 0.2 cm.
What is the hyperfocal distance for 300mm f/4?
750 m (2462 ft) on full frame. Everything from 375 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources