Canon EOS R6 Diffraction Limit
With a 720 nm infrared filter, the Canon EOS R6 stays free of visible diffraction up to ƒ/8, and diffraction starts to soften images at ƒ/12.7. Unconverted (hot mirror), it is diffraction-free up to ƒ/11 and soft from ƒ/18. These limits come from its 6.58 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 R6 in the calculator
Canon EOS R6 specifications
- Pixel pitch: 6.58 μm
- Megapixels: 20.1
- Pixels: 5472 × 3648
- Sensor: Full Frame, 36.0 × 24.0 mm
Buy the Canon EOS R6: KEH Adorama B&H
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/8 | ƒ/10.1 | ƒ/12.7 |
| Hot mirror or UV/IR cut | ƒ/11 | ƒ/12.7 | ƒ/18 |
| 470 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 550 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 590 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 665 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 720 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 780 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 830 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 930 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 1000 nm high-pass | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| IR Chrome | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| UV Bandpass | ƒ/20.2 | ƒ/22 | ƒ/32 |
Diffraction ratio at each ƒ-stop
The Airy disk diameter divided by the 6.58 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 | 0.18 | 0.21 | 0.24 | 0.29 | 0.31 | 0.35 | 0.37 | 0.4 | 0.43 | 0.48 | 0.52 |
| ƒ/2 | 0.26 | 0.3 | 0.35 | 0.41 | 0.44 | 0.49 | 0.53 | 0.58 | 0.62 | 0.69 | 0.74 |
| ƒ/2.8 | 0.36 | 0.42 | 0.49 | 0.57 | 0.61 | 0.69 | 0.75 | 0.81 | 0.86 | 0.97 | 1.04 |
| ƒ/4 | 0.52 | 0.59 | 0.7 | 0.82 | 0.88 | 0.99 | 1.07 | 1.16 | 1.23 | 1.38 | 1.48 |
| ƒ/5.6 | 0.73 | 0.83 | 0.98 | 1.14 | 1.23 | 1.38 | 1.5 | 1.62 | 1.72 | 1.93 | 2.08 |
| ƒ/8 | 1.04 | 1.19 | 1.39 | 1.63 | 1.75 | 1.97 | 2.14 | 2.31 | 2.46 | 2.76 | 2.97 |
| ƒ/11 | 1.43 | 1.63 | 1.92 | 2.24 | 2.41 | 2.71 | 2.94 | 3.18 | 3.39 | 3.79 | 4.08 |
| ƒ/16 | 2.08 | 2.37 | 2.79 | 3.26 | 3.5 | 3.95 | 4.27 | 4.63 | 4.92 | 5.52 | 5.93 |
| ƒ/22 | 2.86 | 3.26 | 3.83 | 4.49 | 4.81 | 5.43 | 5.87 | 6.36 | 6.77 | 7.59 | 8.16 |
| ƒ/32 | 4.15 | 4.75 | 5.58 | 6.53 | 7 | 7.89 | 8.54 | 9.26 | 9.85 | 11.04 | 11.87 |
| 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 R6. The same pixel pitch gives the same diffraction limits.
- Canon EOS 6D (6.54 μm)
- Nikon D5 (6.45 μm)
- 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.