Both the Nikon D3X and Sony Alpha 850 have more than 24.5 million pixels, yet the D3X costs around u00a33,100 more. Richard Sibley finds out what you get for the extra cash in our Nikon D3X vs Sony Alpha 850 test
Nikon D3X vs Sony Alpha 850 – Dynamic Range
It is no real surprise that both the Nikon D3X and Sony Alpha 850 have the same dynamic range. However, the fact that the dynamic range is 12EV is quite surprising, given that each sensor has more than 24 million photosites. Usually the smaller photosites required to create these densely populated sensors collect less light, which impacts upon the amount of information that can be recorded. This, in turn, will affect the dynamic range, particularly in darker shadow areas.
Both cameras have dynamic range optimisation systems in the form of Active D-Lighting in the D3X and D-R Optimiser in the Alpha 850. The Nikon D3X has the more subtle of the two systems. At its extra-high setting, Sony’s D-R Optimiser creates an effect that looks almost like an HDR image. However, this introduces noise in the shadow areas.
Image: These images show 72ppi sections of images of a resolution chart, captured using matching 105mm macro lenses. We show the section of the resolution chart where the camera starts to fail to reproduce the lines separately.
The higher the number visible in these images, the better the camera’s detail resolution is at the specified sensitivity setting.
This graph shows the brightness values recorded by the test camera when it is used to photograph a stepped graduation wedge. The wedge has transmission values in 1⁄2EV steps ranging from 0 to 12EV. The camera’s exposure is set so the 12EV section in the wedge has a brightness value of 255. Software analysis of the image then determines the recorded brightness values of all the other steps and calculates the camera’s dynamic range.