Think that the Nikon D810 is high resolution? Think again. Canon has unveiled the EOS 5DS and 5DS R models, each boasting a 50.6-megapixel full-frame sensor at their core, making them the highest-resolution DSLR cameras on the market.

So what's the difference between the two? Both cameras are built around the same 5D Mark III body (with minor tweaks to grip and style), but the R has a dual low-pass filter (LPF) system, which is said to act like a LPF-free solution for sharper images.

Design

Exterior design differences come down to the name badges only: the 5DS opts for a golden finish, the 5DS R a silver and red badge.

Both models are built around the weather-proofed 152.0 x 116.4 x 76.4mm footprint of the earlier 5D Mark III body. There's a new base plate and different mirror box assembly than the older Mk III model, to incorporate a mirror vibration control system to ensure limited affect from the mirror - an essential at this ultra-high resolution.

Compared to the Mk III there's also a subtle left-hand grip, to make for better two-handed holding, again for added stability.

Sensor

The sensor found in both models is one and the same, a 50.6-megapixel full-frame (36 x 24mm / 35mm film equivalent) sensor, matched with dual Digic 6 processors for fast processing.

The difference is the 5DS utilises a low-pass filter (LPF), to diffuse light and avoid moire and false colour effects (although, at this resolution, we're not convinced it's a necessary feature).

The 5DS R, on the other hand, is trying to achieve a LPF-free result by using two low-pass filters - one to counteract the first's effects. Sounds a bit bonkers, why not just remove the filter altogether? But then the focal plane of the sensor would have to be adjusted to achieve accurate focus, and as the 5DS R is built around the 5D MkIII's frame, it's had to employ a different work-around. Which makes it sound like a last-minute decision in many respects.

The result of the 5DS R, according to Canon, is sharper images, but with greater risk of moire in some scenarios. Great for many landscapes, not so good for shooting pin-stripe suits in the studio.

Autofocus & speed

Adopting the same 61-point autofocus system as found in the 5D MkIII reaps the same fast results. However, at this 50-megapixel resolution there's a greater chance of soft images if you go about shooting as you would with an 18-megapixel camera. Any given subject will lie across a greater number of pixels, so subtle movements have a greater impact to results - higher shutter speeds, slower subject movement, and better camera stability are all ways to counteract such effects.

A point of difference compared to the 5D MkIII, however, is that 1.6x and 1.3x crop options deliver respective 19- and 30-megapixel results, but benefit from a tighter autofocus arrangement within the active viewfinder area. So with 1.6x selected, the autofocus arrangement covers the majority of the frame.

Impressively both models can snap five frames per second (5fps) at full resolution thanks to the dual Digic 6 processors.

Movie

However, despite the considerable buffer Canon does not offer 4K movie capture. Instead it's 1080p Full HD available at the full range of 60/50/30/25/24fps.

With the focus on being stills cameras, the 3.5mm headphone monitoring port found in the 5D MkIII has gone, replaced in both 5DS and 5DS R by a USB 3.0 output for fast transfer of images.

Price and release date

The other crucial difference is price. The 5DS will be priced £3,000 body-only, while the 5DS R adds an extra £200 to the asking price. Both models will be available June 2015.