Medium format (44×33) depth of field & hyperfocal charts
Digital medium format (about 43.8 × 32.9 mm) — Fujifilm GFX, Hasselblad X and Pentax 645 — has a crop factor of 0.79×: the sensor is larger than full frame. It uses a 0.038 mm circle of confusion for depth of field.
Advanced
Leave empty to use the standard value for the sensor. Halve it for pixel-level sharpness.
With a 63 mm lens at f/2.8 on medium format focused at 3.00 m, everything from 2.78 m to 3.26 m is acceptably sharp: 48 cm of depth of field.
- In front of subject
- 22 cm (46%)
- Behind subject
- 26 cm (54%)
- Hyperfocal distance
- 37.4 m
- Circle of confusion
- 0.038 mm
About the Medium Format format
Focal lengths look wider than on full frame: a 63 mm lens frames like 50 mm and a 110 mm like 87 mm. At the same framing and f-number depth of field is about two-thirds of a stop shallower than full frame, which, together with very high resolution, gives medium format its distinctive three-dimensional look.
The circle of confusion is 0.038 mm by the standard print convention, but with 100 MP sensors most landscape photographers work to a much smaller value, stopping down to f/8–f/11 and focus stacking where needed.
Specifications
| Property | Value |
|---|---|
| Sensor size | 43.8 × 32.9 mm |
| Diagonal | 54.8 mm |
| Crop factor | 0.79× |
| Circle of confusion | 0.038 mm |
| Area vs full frame | 167% |
| Typical cameras | Fujifilm GFX, Hasselblad X2D / 907X, Pentax 645Z |
Hyperfocal distance chart
Focus at the distance shown and everything from half of it to infinity is acceptably sharp (c = 0.038 mm).
| Focal length | f/2.8 | f/4 | f/5.6 | f/8 | f/11 | f/16 |
|---|---|---|---|---|---|---|
| 20 mm | 3.78 m12.4 ft | 2.65 m8.70 ft | 1.90 m6.23 ft | 1.34 m4.38 ft | 98 cm3.21 ft | 68 cm2.22 ft |
| 23 mm | 4.99 m16.4 ft | 3.50 m11.5 ft | 2.51 m8.23 ft | 1.76 m5.78 ft | 1.29 m4.23 ft | 89 cm2.93 ft |
| 32 mm | 9.66 m31.7 ft | 6.77 m22.2 ft | 4.84 m15.9 ft | 3.40 m11.2 ft | 2.48 m8.14 ft | 1.72 m5.63 ft |
| 45 mm | 19.1 m62.6 ft | 13.4 m43.9 ft | 9.56 m31.4 ft | 6.71 m22.0 ft | 4.89 m16.0 ft | 3.38 m11.1 ft |
| 63 mm | 37.4 m123 ft | 26.2 m85.9 ft | 18.7 m61.4 ft | 13.1 m43.0 ft | 9.56 m31.4 ft | 6.59 m21.6 ft |
| 80 mm | 60.2 m198 ft | 42.2 m138 ft | 30.2 m98.9 ft | 21.1 m69.3 ft | 15.4 m50.5 ft | 10.6 m34.8 ft |
| 110 mm | 114 m373 ft | 79.7 m262 ft | 57.0 m187 ft | 39.9 m131 ft | 29.1 m95.3 ft | 20.0 m65.7 ft |
Equivalent focal length and aperture
Multiply by 0.79 to compare with full frame. The aperture equivalent describes depth of field and total light; exposure settings do not change.
| Lens on this sensor | Full-frame focal length | f/2.8 looks like | f/4 looks like |
|---|---|---|---|
| 20 mm | 16 mm | f/2.2 | f/3.2 |
| 23 mm | 18 mm | f/2.2 | f/3.2 |
| 32 mm | 25 mm | f/2.2 | f/3.2 |
| 45 mm | 36 mm | f/2.2 | f/3.2 |
| 63 mm | 50 mm | f/2.2 | f/3.2 |
| 80 mm | 63 mm | f/2.2 | f/3.2 |
| 110 mm | 87 mm | f/2.2 | f/3.2 |
Night sky: 500 rule and NPF rule
Longest exposure before stars trail at f/2.8 with 100 MP (pixel pitch 3.80 µm). Calculate for your own camera with the 500 rule & NPF calculator.
| Focal length | 500 rule | 300 rule | NPF rule |
|---|---|---|---|
| 20 mm | 32 s | 19 s | 11 s |
| 23 mm | 28 s | 17 s | 9.2 s |
| 32 mm | 20 s | 12 s | 6.6 s |
| 45 mm | 14 s | 8.4 s | 4.7 s |
| 63 mm | 10 s | 6 s | 3.4 s |
| 80 mm | 7.9 s | 4.7 s | 2.6 s |
| 110 mm | 5.8 s | 3.5 s | 1.9 s |
FAQ
What is the crop factor of a Medium Format sensor?
0.79×. The 43.8 × 32.9 mm sensor has a 54.8 mm diagonal, compared with 43.3 mm for full frame, so a 63 mm lens frames like 50 mm on full frame.
What circle of confusion should I use for Medium Format?
0.038 mm, the sensor diagonal divided by 1443 — the same convention as lens depth of field scales and DOFMaster. Use about half (0.019 mm) if you view images at 100% or print very large.
What is the hyperfocal distance of a 23 mm lens on Medium Format?
1.76 m (5.78 ft) at f/8. Focus there and everything from half that distance to infinity is acceptably sharp.
How long can I expose the night sky on Medium Format?
With a 23 mm lens at f/2.8 and 100 MP (pixel pitch 3.8 µm), about 9.2 s by the NPF rule, or 28 s by the 500 rule.