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 – Features
The headline feature of these cameras has to be their high-resolution, full-frame sensors. The Nikon D3X has a 24.5-million-effective-pixel CMOS sensor, while the Sony Alpha 850 has a slightly more densely packed 24.6-million-effective-pixel CMOS sensor. Interestingly, the output resolution of both cameras is 6048×4032 pixels, making an identical 24,385,536 total pixel output for both cameras.
Nikon USA has openly stated that the sensor in the D3X was manufactured by Sony, but based on a design Nikon developed specifically for the D3X camera. This has led many to believe that the same sensor is used in the Sony Alpha 850, and while it is safe to assume they have much in common, the architecture surrounding the sensor is different. For example, the microlenses that direct light onto the sensor’s photosites, the low-pass filter above the sensor array, as well as the analogue-to-digital conversion systems may all be different, and each of these individual components will affect the image quality.
Each manufacturer also has its own image-processing engine. In the D3X, Nikon has fitted its Expeed processing system, while Sony has installed its dual Bionz engine in the Alpha 850. How these different image-processing engines process the data passed on from the sensor will affect image quality. So, even though the two cameras share a similar starting point, the images they produce may be very different.
The Sony Alpha 850 is a cut-down version of its big brother, the Alpha 900. One of the main differences between the two Alpha cameras is the continuous shooting rate, which is 5fps with the Alpha 900 and 3fps with the Alpha 850. This is the same as the difference in shooting rate between the Alpha 850 and the Nikon D3X, as the D3X also has a continuous shooting rate of 5fps. Given that neither camera is designed with sports photographers or photojournalists in mind, this shouldn’t concern many photographers. With resolutions in excess of 24 million pixels, both the Alpha 850 and D3X are really designed to capture detail in a studio or landscape environment.
With the Nikon D3X costing £3,100 more than the Sony Alpha 850, you’d think that the D3X would be packed full of features not present in the less expensive camera. However, there is one major feature that the Alpha 850 has that the D3X doesn’t: in-camera sensor-shift image stabilisation, or SteadyShot Inside as Sony has branded it. Nikon uses lens-based image stabilisation in its cameras, with an increasing number of lenses having VR (Vibration Reduction) built in.
Having image stabilisation built directly into the camera has the advantage that it will work with any lens. Nikon’s 24-70mm lens, for example, lacks Vibration Reduction, whereas this isn’t a concern with Sony’s equivalent 24-70mm f/2.8 ZA SSMVario-Sonnar T* lens as the stabilisation is in-camera.
The Alpha 850’s sensor-shift image stabilisation offers another advantage over the Nikon D3X – it can also be used as a sensor-cleaning system by vibrating dust away from the sensor. Nikon omitted a sensor-cleaning system from the D3 and D3X, claiming it would have affected the 100% viewfinder coverage.
One feature noticeably absent from the Sony Alpha 850 is Live View, which is surprising considering that it is now found in most cameras, including the Nikon D3X.
When it comes to the main features of both the Alpha 850 and the D3X, there isn’t a lot to separate them, and certainly not enough to warrant parting with an extra £3,100. In fact, the sensor-shift image stabilisation of the Alpha 850 and the extra 2-4EV exposure time it allows is arguably a more valuable feature than Live View or an extra 2fps continuous shooting rate.