DIFFRACTION Nikon D800

DIFFRACTION Nikon D800

DIFFRACTION

MOTION BLUR

NIKON D800 DYNAMIC RANGE

NOISE – ISO PERFORMANCE
Brian Tobey





So where does diffraction begin to impact the D800? Well first we need to know the pixel size. This can be approximated by dividing the sensor size by the number of pixels on a per axis basis.


THE MATH
According to these theoretical approximations, we conclude that ideally we would want to shoot the D800 at f/8 or below in order to prevent diffraction from softening pictures. However, the calculation is flawed in that in accounts for only a single frequency. In our case, we selected 500nm wavelength, which is the color green, the most sensitive to our eyes, to replicate daylight. However, daylight has many colors or frequencies and therefore we must consider the entire bandwidth. This calculation becomes more complicated, but when analyzed across a bandwidth, diffraction becomes more forgiving, which means we can shoot the D800 up to f/11 and be perfectly satisfied with the results!

Note that recently announced Nikon D3200 has an even denser sensor, with 24.2 MP on a DX size sensor. It becomes diffraction limited around f/6.3. This is of more concern than the D800, as most DX lenses are not optimal until f/8. To maximize the quality of the D3200, I’d shoot at f/5.6 and stick with the Nikon 35mm f/1.8G or 50mm f/1.8G. I have always been a fan of those lenses. And if you notice, Nikon shot a lot of the sample images at f/5.6 using some expensive glass.






dynamic range