Micro Nikkor AF-S DX 40mm f/2.8 G (CX) - Review / Test Report - Analysis
Lens Reviews - Nikon CX
Wednesday, 22 October 2008 17:06


In its native use on a DX camera the Nikkor already exhibits very little image distortion. Consequently, it's no surprise that the lens shows virtually no distortion on a CX sensor camera.

The chart above has a real-world size of about 120x80cm.


Just like distortion, vignetting is no issue on CX cameras.

MTF (resolution)

The lens already delivers excellent resolution in the image center at the largest aperture setting. The center resolution remains on this high level, until diffraction reduces image sharpness at f/11 and much more so at f/16 and beyond.

The borders and corners struggle a bit at large aperture settings, the lens needs to be stopped down to f/5.6 or f/8 to achieve very good sharpness across the whole frame.

Below is a simplified summary of the formal findings. The chart shows line widths per picture height (LW/PH) which can be taken as a measure for sharpness. If you want to know more about the MTF50 figures you may check out the corresponding Imatest Explanations

Chromatic Aberrations (CAs)

Chromatic aberrations (color shadows at harsh contrast transitions) are moderate at large aperture, but increase to higher values by stopping down, reaching up to 1.5 pixels at the image border at f/22. This might be visible in very large prints (or crops). However, CAs can easily be corrected in software, in fact the Nikon 1 cameras automatically do so if you shoot JPGs.