Sony α7 Diffraction Limit
With a 720 nm infrared filter, the Sony α7 stays free of visible diffraction up to ƒ/7.1, and diffraction starts to soften images at ƒ/11. Unconverted (hot mirror), it is diffraction-free up to ƒ/10.1 and soft from ƒ/16. These limits come from its 5.97 μm pixel pitch: longer infrared wavelengths make a larger Airy disk, so diffraction appears at wider apertures than in visible light.
Open the Sony α7 in the calculator
Sony α7 specifications
- Pixel pitch: 5.97 μm
- Megapixels: 24.3
- Pixels: 6000 × 4000
- Sensor: Full Frame, 35.8 × 23.9 mm
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/11 |
| Hot mirror or UV/IR cut | ƒ/10.1 | ƒ/12.7 | ƒ/16 |
| 470 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 550 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 590 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 665 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 720 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 780 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 830 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 930 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| 1000 nm high-pass | ƒ/7.1 | ƒ/9 | ƒ/11 |
| IR Chrome | ƒ/7.1 | ƒ/9 | ƒ/11 |
| UV Bandpass | ƒ/18 | ƒ/22 | ƒ/28.5 |
Diffraction ratio at each ƒ-stop
The Airy disk diameter divided by the 5.97 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 | 0.2 | 0.23 | 0.27 | 0.31 | 0.34 | 0.38 | 0.41 | 0.45 | 0.47 | 0.53 | 0.57 |
| ƒ/2 | 0.29 | 0.33 | 0.38 | 0.45 | 0.48 | 0.54 | 0.59 | 0.64 | 0.68 | 0.76 | 0.82 |
| ƒ/2.8 | 0.4 | 0.46 | 0.54 | 0.63 | 0.68 | 0.76 | 0.82 | 0.89 | 0.95 | 1.06 | 1.14 |
| ƒ/4 | 0.57 | 0.65 | 0.77 | 0.9 | 0.96 | 1.09 | 1.18 | 1.28 | 1.36 | 1.52 | 1.63 |
| ƒ/5.6 | 0.8 | 0.92 | 1.08 | 1.26 | 1.35 | 1.52 | 1.65 | 1.79 | 1.9 | 2.13 | 2.29 |
| ƒ/8 | 1.14 | 1.31 | 1.54 | 1.8 | 1.93 | 2.17 | 2.35 | 2.55 | 2.71 | 3.04 | 3.27 |
| ƒ/11 | 1.57 | 1.8 | 2.11 | 2.47 | 2.65 | 2.99 | 3.24 | 3.51 | 3.73 | 4.18 | 4.5 |
| ƒ/16 | 2.29 | 2.62 | 3.07 | 3.6 | 3.86 | 4.35 | 4.71 | 5.1 | 5.43 | 6.08 | 6.54 |
| ƒ/22 | 3.15 | 3.6 | 4.23 | 4.95 | 5.31 | 5.98 | 6.47 | 7.01 | 7.46 | 8.36 | 8.99 |
| ƒ/32 | 4.58 | 5.23 | 6.15 | 7.19 | 7.72 | 8.7 | 9.42 | 10.2 | 10.86 | 12.16 | 13.08 |
| 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 α7. The same pixel pitch gives the same diffraction limits.
- Nikon D600 (5.97 μm)
- Nikon D610 (5.97 μm)
- Nikon D750 (5.97 μm)
- Nikon Z 5 (5.97 μm)
- Sony Cyber-shot DSC-RX1 (5.97 μm)
- Sony Cyber-shot DSC-RX1R (5.97 μm)
Pixel pitch comes from the camera database. Send a correction if anything here is wrong.