Canon EOS 5D Mark III Diffraction Limit
With a 720 nm infrared filter, the Canon EOS 5D Mark III stays free of visible diffraction up to ƒ/7.1, and diffraction starts to soften images at ƒ/12.7. Unconverted (hot mirror), it is diffraction-free up to ƒ/10.1 and soft from ƒ/16. These limits come from its 6.25 μm pixel pitch: longer infrared wavelengths make a larger Airy disk, so diffraction appears at wider apertures than in visible light.
Open the Canon EOS 5D Mark III in the calculator
Canon EOS 5D Mark III specifications
- Pixel pitch: 6.25 μm
- Megapixels: 22.3
- Pixels: 5760 × 3840
- Sensor: Full Frame, 36.0 × 24.0 mm
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Sharpest ƒ-stop by filter
Safe is the narrowest aperture with a diffraction ratio of 3 or lower at every wavelength the filter passes. Caution allows up to 3.75. Avoid is the first aperture where any wavelength reaches 4.5. All three are calculated to the one-third stop. See which wavelengths each filter passes.
| Filter | Safe | Caution | Avoid |
|---|---|---|---|
| Full spectrum | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| Hot mirror or UV/IR cut | ƒ/10.1 | ƒ/12.7 | ƒ/16 |
| 470 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 550 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 590 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 665 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 720 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 780 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 830 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 930 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| 1000 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| IR Chrome | ƒ/7.1 | ƒ/9 | ƒ/12.7 |
| UV Bandpass | ƒ/18 | ƒ/22 | ƒ/32 |
Diffraction ratio at each ƒ-stop
The Airy disk diameter divided by the 6.25 μm pixel pitch, for every wavelength from ultraviolet to infrared. A filter only passes some of these wavelengths; the table above applies each filter’s set. How the ratio is calculated.
| ƒ-stop | 350 nm | 400 nm | 470 nm | 550 nm | 590 nm | 665 nm | 720 nm | 780 nm | 830 nm | 930 nm | 1000 nm |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ƒ/1.4 | 0.19 | 0.22 | 0.26 | 0.3 | 0.32 | 0.36 | 0.39 | 0.43 | 0.45 | 0.51 | 0.55 |
| ƒ/2 | 0.27 | 0.31 | 0.37 | 0.43 | 0.46 | 0.52 | 0.56 | 0.61 | 0.65 | 0.73 | 0.78 |
| ƒ/2.8 | 0.38 | 0.44 | 0.51 | 0.6 | 0.64 | 0.73 | 0.79 | 0.85 | 0.91 | 1.02 | 1.09 |
| ƒ/4 | 0.55 | 0.62 | 0.73 | 0.86 | 0.92 | 1.04 | 1.12 | 1.22 | 1.3 | 1.45 | 1.56 |
| ƒ/5.6 | 0.77 | 0.87 | 1.03 | 1.2 | 1.29 | 1.45 | 1.57 | 1.71 | 1.81 | 2.03 | 2.19 |
| ƒ/8 | 1.09 | 1.25 | 1.47 | 1.72 | 1.84 | 2.08 | 2.25 | 2.44 | 2.59 | 2.9 | 3.12 |
| ƒ/11 | 1.5 | 1.72 | 2.02 | 2.36 | 2.53 | 2.86 | 3.09 | 3.35 | 3.56 | 3.99 | 4.29 |
| ƒ/16 | 2.19 | 2.5 | 2.94 | 3.44 | 3.69 | 4.15 | 4.5 | 4.87 | 5.18 | 5.81 | 6.25 |
| ƒ/22 | 3.01 | 3.44 | 4.04 | 4.72 | 5.07 | 5.71 | 6.18 | 6.7 | 7.13 | 7.99 | 8.59 |
| ƒ/32 | 4.37 | 5 | 5.87 | 6.87 | 7.37 | 8.31 | 8.99 | 9.74 | 10.37 | 11.62 | 12.49 |
| No visible diffraction (less than 3) | |
| Visible diffraction may slightly impact image sharpness (3 to 4.5) | |
| Visible diffraction will impact image sharpness (4.5 or greater) |
Cameras with similar pixel pitch
Other Full Frame cameras within 0.2 μm of the Canon EOS 5D Mark III. The same pixel pitch gives the same diffraction limits.
- Canon EOS 1Ds Mark III (6.41 μm)
- Canon EOS 5D Mark II (6.41 μm)
Pixel pitch comes from the camera database. Send a correction if anything here is wrong.