Depth of field by subject distance#
105 mm at f/1.8 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) | 30.0 cm | 30.0 cm | 0.1 cm | 50% / 50% | 87.25% |
| 50.0 cm (1.64 ft) | 49.9 cm | 50.1 cm | 0.2 cm | 50% / 50% | 43.07% |
| 75.0 cm (2.46 ft) | 74.8 cm | 75.2 cm | 0.5 cm | 50% / 50% | 26.38% |
| 1.00 m (3.28 ft) | 99.6 cm | 1.00 m | 0.9 cm | 50% / 50% | 19.01% |
| 1.50 m (4.92 ft) | 1.49 m | 1.51 m | 2.0 cm | 50% / 50% | 12.20% |
| 2.00 m (6.56 ft) | 1.98 m | 2.02 m | 3.7 cm | 50% / 50% | 8.98% |
| 3.00 m (9.84 ft) | 2.96 m | 3.04 m | 8.5 cm | 49% / 51% | 5.88% |
| 4.00 m (13.1 ft) | 3.93 m | 4.08 m | 15.3 cm | 49% / 51% | 4.37% |
| 5.00 m (16.4 ft) | 4.88 m | 5.12 m | 24.0 cm | 49% / 51% | 3.48% |
| 7.00 m (23.0 ft) | 6.77 m | 7.24 m | 47.3 cm | 48% / 52% | 2.47% |
| 10.0 m (32.8 ft) | 9.54 m | 10.5 m | 97.2 cm | 48% / 52% | 1.72% |
| 15.0 m (49.2 ft) | 14.0 m | 16.2 m | 2.20 m | 46% / 54% | 1.14% |
| 20.0 m (65.6 ft) | 18.2 m | 22.2 m | 3.94 m | 45% / 55% | 0.86% |
| 30.0 m (98.4 ft) | 26.2 m | 35.1 m | 8.98 m | 43% / 57% | 0.57% |
| 50.0 m (164 ft) | 40.2 m | 66.2 m | 26.0 m | 38% / 62% | 0.34% |
| 100 m (328 ft) | 67.1 m | 196 m | 129 m | 26% / 74% | 0.17% |
Try other settings#
105 mm at other apertures (subject at 3 m)#
Other focal lengths at f/1.8#
Same lens settings on other formats#
When to use it#
At f/1.8, a 105 mm lens on full frame is a natural choice for portraits and subject isolation. Focused at 3 m you get 8.5 cm of sharp zone; for maximum front-to-back sharpness focus at 204 m and everything from 102 m to infinity will be acceptably sharp.
See also the f/1.8 aperture guide.
Frequently asked questions#
What is the depth of field of a 105mm lens at f/1.8?
On full frame, focused at 3 m, it is 8.5 cm; at 1 m it is 0.9 cm.
What is the hyperfocal distance for 105mm f/1.8?
204 m (670 ft) on full frame. Everything from 102 m to infinity is acceptably sharp.
Last updated October 03, 2026 · How we calculate · Sources