marcsantacurz
Well-known member
I think an important thing to keep in mind is that as the pixel pitch gets smaller, the maximum allowable airy disc (circle of confusion) also gets smaller. The numbers below are from some back-of-the-envelope estimates of sensor resolving power, so they might be off by a small amount.
On the d850, the pixel pitch is about 4.3um so the largest CoC you want is about 10.7um (about 2.5x the pixel pitch, due to bayer interpolation), so diffraction limiting begins around f/8 and will get bad by f/16-f/22.
On the a7r4, the pixel pitch is about 3.7um, so the largest CoC you want is about 9.3um. Diffraction limiting will begin around f/5.6-6.3 and will get bad by f/12-16.
This also means that smaller and smaller amounts of shake will cause the airy disc to wobble over other sensor sites. This will cause a loss of micro-contrast and blur.
The Fuji GFX 50 has a 51.4 MP sensor with about a 5.3u pitch. It will start getting diffraction limited around f/16 and get bad maybe around f/22-30.
If you do not pixel peep, you will not notice it unless you made a very very large print or crop a lot. Smaller pixels will show fewer artifacts from crossing the diffraction boundary. Also, the 61MP sensor, even if slightly blurred from diffraction, will still behave like a 30 - 40 MP sensor if you are not pixel peeping. Higher MP sensors will always show more detail (same size sensors) and software sharpening can help a lot, but you will lose the finest sharpness at lower f-stops.
Steve Perry has a nice video on this: https://youtu.be/N0FXoWdHXTk
On the d850, the pixel pitch is about 4.3um so the largest CoC you want is about 10.7um (about 2.5x the pixel pitch, due to bayer interpolation), so diffraction limiting begins around f/8 and will get bad by f/16-f/22.
On the a7r4, the pixel pitch is about 3.7um, so the largest CoC you want is about 9.3um. Diffraction limiting will begin around f/5.6-6.3 and will get bad by f/12-16.
This also means that smaller and smaller amounts of shake will cause the airy disc to wobble over other sensor sites. This will cause a loss of micro-contrast and blur.
The Fuji GFX 50 has a 51.4 MP sensor with about a 5.3u pitch. It will start getting diffraction limited around f/16 and get bad maybe around f/22-30.
If you do not pixel peep, you will not notice it unless you made a very very large print or crop a lot. Smaller pixels will show fewer artifacts from crossing the diffraction boundary. Also, the 61MP sensor, even if slightly blurred from diffraction, will still behave like a 30 - 40 MP sensor if you are not pixel peeping. Higher MP sensors will always show more detail (same size sensors) and software sharpening can help a lot, but you will lose the finest sharpness at lower f-stops.
Steve Perry has a nice video on this: https://youtu.be/N0FXoWdHXTk