Micro Four Thirds depth of field & hyperfocal charts
Micro Four Thirds (17.3 × 13 mm) is the format of OM System and Panasonic Lumix G cameras, with an exact 2× crop factor and a squarer 4:3 shape. It uses a 0.015 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 25 mm lens at f/2.8 on Micro Four Thirds focused at 3.00 m, everything from 2.50 m to 3.75 m is acceptably sharp: 1.25 m of depth of field.
- In front of subject
- 50 cm (40%)
- Behind subject
- 75 cm (60%)
- Hyperfocal distance
- 14.9 m
- Circle of confusion
- 0.015 mm
About the Micro Four Thirds format
The 2× crop makes the maths easy: a 25 mm lens frames like 50 mm, a 12 mm like 24 mm and a 300 mm like 600 mm, which is why the system is loved by wildlife and travel photographers. At the same framing and f-number you get two stops more depth of field than full frame, so f/4 on Micro Four Thirds looks like f/8 on full frame — great for landscapes and macro, while fast f/1.2–f/1.8 primes bring back background blur.
The circle of confusion is 0.015 mm. Diffraction becomes visible earlier, from about f/5.6–f/8, so the hyperfocal charts below stop at f/11.
Specifications
| Property | Value |
|---|---|
| Sensor size | 17.3 × 13 mm |
| Diagonal | 21.6 mm |
| Crop factor | 2× |
| Circle of confusion | 0.015 mm |
| Area vs full frame | 26% |
| Typical cameras | OM System OM-1, Panasonic Lumix G9 II / GH7, DJI Mavic 3 |
Hyperfocal distance chart
Focus at the distance shown and everything from half of it to infinity is acceptably sharp (c = 0.015 mm).
| Focal length | f/1.8 | f/2.8 | f/4 | f/5.6 | f/8 | f/11 |
|---|---|---|---|---|---|---|
| 7 mm | 1.82 m5.98 ft | 1.17 m3.85 ft | 82 cm2.70 ft | 59 cm1.94 ft | 42 cm1.36 ft | 30 cm12.0 in |
| 8 mm | 2.38 m7.80 ft | 1.53 m5.03 ft | 1.07 m3.53 ft | 77 cm2.53 ft | 54 cm1.78 ft | 40 cm1.30 ft |
| 12 mm | 5.35 m17.5 ft | 3.44 m11.3 ft | 2.41 m7.91 ft | 1.73 m5.66 ft | 1.21 m3.98 ft | 88 cm2.90 ft |
| 15 mm | 8.35 m27.4 ft | 5.37 m17.6 ft | 3.77 m12.4 ft | 2.69 m8.84 ft | 1.89 m6.20 ft | 1.38 m4.52 ft |
| 17 mm | 10.7 m35.2 ft | 6.90 m22.6 ft | 4.83 m15.9 ft | 3.46 m11.3 ft | 2.43 m7.96 ft | 1.77 m5.80 ft |
| 20 mm | 14.8 m48.7 ft | 9.54 m31.3 ft | 6.69 m21.9 ft | 4.78 m15.7 ft | 3.35 m11.0 ft | 2.44 m8.02 ft |
| 25 mm | 23.2 m76.0 ft | 14.9 m48.9 ft | 10.4 m34.3 ft | 7.47 m24.5 ft | 5.23 m17.2 ft | 3.81 m12.5 ft |
| 45 mm | 75.0 m246 ft | 48.3 m158 ft | 33.8 m111 ft | 24.2 m79.2 ft | 16.9 m55.5 ft | 12.3 m40.4 ft |
| 75 mm | 208 m684 ft | 134 m440 ft | 93.8 m308 ft | 67.0 m220 ft | 47.0 m154 ft | 34.2 m112 ft |
Equivalent focal length and aperture
Multiply by 2 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/1.8 looks like | f/2.8 looks like |
|---|---|---|---|
| 7 mm | 14 mm | f/3.6 | f/5.6 |
| 8 mm | 16 mm | f/3.6 | f/5.6 |
| 12 mm | 24 mm | f/3.6 | f/5.6 |
| 15 mm | 30 mm | f/3.6 | f/5.6 |
| 17 mm | 34 mm | f/3.6 | f/5.6 |
| 20 mm | 40 mm | f/3.6 | f/5.6 |
| 25 mm | 50 mm | f/3.6 | f/5.6 |
| 45 mm | 90 mm | f/3.6 | f/5.6 |
| 75 mm | 150 mm | f/3.6 | f/5.6 |
Night sky: 500 rule and NPF rule
Longest exposure before stars trail at f/1.8 with 20 MP (pixel pitch 3.35 µm). Calculate for your own camera with the 500 rule & NPF calculator.
| Focal length | 500 rule | 300 rule | NPF rule |
|---|---|---|---|
| 7 mm | 36 s | 21 s | 23 s |
| 8 mm | 31 s | 19 s | 20 s |
| 12 mm | 21 s | 13 s | 14 s |
| 15 mm | 17 s | 10 s | 11 s |
| 17 mm | 15 s | 8.8 s | 9.6 s |
| 20 mm | 13 s | 7.5 s | 8.2 s |
| 25 mm | 10 s | 6 s | 6.5 s |
| 45 mm | 5.6 s | 3.3 s | 3.6 s |
| 75 mm | 3.3 s | 2 s | 2.2 s |
FAQ
What is the crop factor of a Micro Four Thirds sensor?
2×. The 17.3 × 13 mm sensor has a 21.6 mm diagonal, compared with 43.3 mm for full frame, so a 25 mm lens frames like 50 mm on full frame.
What circle of confusion should I use for Micro Four Thirds?
0.015 mm, the sensor diagonal divided by 1443 — the same convention as lens depth of field scales and DOFMaster. Use about half (0.007 mm) if you view images at 100% or print very large.
What is the hyperfocal distance of a 8 mm lens on Micro Four Thirds?
77 cm (2.53 ft) at f/5.6. Focus there and everything from half that distance to infinity is acceptably sharp.
How long can I expose the night sky on Micro Four Thirds?
With a 8 mm lens at f/1.8 and 20 MP (pixel pitch 3.4 µm), about 20 s by the NPF rule, or 31 s by the 500 rule.
Cameras with this sensor size
Exact crop factors and lens equivalents from each camera’s published sensor size: