Sony α7R Diffraction Limit
With a 720 nm infrared filter, the Sony α7R stays free of visible diffraction up to ƒ/5.6, and diffraction starts to soften images at ƒ/9. Unconverted (hot mirror), it is diffraction-free up to ƒ/8 and soft from ƒ/12.7. These limits come from its 4.88 μm pixel pitch: longer infrared wavelengths make a larger Airy disk, so diffraction appears at wider apertures than in visible light.
Open the Sony α7R in the calculator
Sony α7R specifications
- Pixel pitch: 4.88 μm
- Megapixels: 36.4
- Pixels: 7360 × 4912
- Sensor: Full Frame, 35.9 × 24.0 mm
Buy the Sony α7R: 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/5.6 | ƒ/7.1 | ƒ/9 |
| Hot mirror or UV/IR cut | ƒ/8 | ƒ/10.1 | ƒ/12.7 |
| 470 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 550 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 590 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 665 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 720 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 780 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 830 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 930 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| 1000 nm high-pass | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| IR Chrome | ƒ/5.6 | ƒ/7.1 | ƒ/9 |
| UV Bandpass | ƒ/14.3 | ƒ/18 | ƒ/25.4 |
Diffraction ratio at each ƒ-stop
The Airy disk diameter divided by the 4.88 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 | 0.24 | 0.28 | 0.33 | 0.39 | 0.41 | 0.47 | 0.5 | 0.55 | 0.58 | 0.65 | 0.7 |
| ƒ/2 | 0.35 | 0.4 | 0.47 | 0.55 | 0.59 | 0.66 | 0.72 | 0.78 | 0.83 | 0.93 | 1 |
| ƒ/2.8 | 0.49 | 0.56 | 0.66 | 0.77 | 0.83 | 0.93 | 1.01 | 1.09 | 1.16 | 1.3 | 1.4 |
| ƒ/4 | 0.7 | 0.8 | 0.94 | 1.1 | 1.18 | 1.33 | 1.44 | 1.56 | 1.66 | 1.86 | 2 |
| ƒ/5.6 | 0.98 | 1.12 | 1.32 | 1.54 | 1.65 | 1.86 | 2.02 | 2.18 | 2.32 | 2.6 | 2.8 |
| ƒ/8 | 1.4 | 1.6 | 1.88 | 2.2 | 2.36 | 2.66 | 2.88 | 3.12 | 3.32 | 3.72 | 4 |
| ƒ/11 | 1.93 | 2.2 | 2.59 | 3.03 | 3.25 | 3.66 | 3.96 | 4.29 | 4.57 | 5.12 | 5.5 |
| ƒ/16 | 2.8 | 3.2 | 3.76 | 4.4 | 4.72 | 5.32 | 5.76 | 6.24 | 6.64 | 7.44 | 8 |
| ƒ/22 | 3.85 | 4.4 | 5.17 | 6.05 | 6.49 | 7.32 | 7.92 | 8.58 | 9.13 | 10.23 | 11 |
| ƒ/32 | 5.6 | 6.4 | 7.52 | 8.8 | 9.44 | 10.64 | 11.52 | 12.48 | 13.28 | 14.88 | 16 |
| 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 Sony α7R. The same pixel pitch gives the same diffraction limits.
- Nikon D800 (4.88 μm)
- Nikon D800E (4.88 μm)
- Nikon D810 (4.88 μm)
- Pentax K-1 (4.88 μm)
- Pentax K-1 Mark II (4.88 μm)
Pixel pitch comes from the camera database. Send a correction if anything here is wrong.