Updated: Best full frame DSLR 2015: Canon vs Nikon vs Sony ~ lotfi

What to look for and which one wins

Camera reviews

Best DSLR 2015

Best camera 2015

Most professional photographers choose a full frame DSLR over any other camera type. They're larger, heavier and certainly more expensive than APS-C format DSLRs, but for full frame fans they're worth it.

Full frame DSLRs aren't just for pros, though. Canon and Nikon make lower cost DSLRs for enthusiasts and experts who want the best possible quality but don't need (or can't afford) full-on professional cameras.

Full frame sensors are twice the size (in area) of the APS-C sensors used in mid-range and entry-level DSLRs, and this gives them a number of advantages:

For a given resolution, a full-frame sensor will have larger photosites (pixels) so you'll get better quality at higher ISOs.

But makers can also use the larger area for higher resolutions without compromising low-light performance – the Nikon D810 has 36 million pixels and the Canon 5DS will have 50 million.

The larger sensor means you use longer focal lengths, and this gives shallower depth of field and more pronounced defocus effects – perfect for portraits, sport shots and any scene where you want to tone down a cluttered background.

All this costs money, however, and not just for the camera itself – you may also need to invest in new lenses, even if you have some already. You can't use Canon EF-S lenses on its full-frame cameras, for example, and while you can use Nikon DX lenses on a Nikon FX full frame camera, they'll only work in 'DX crop' mode, which negates the advantage of the bigger sensor.

If you're not sure, you might want to take a look at some full-frame alternatives instead:

Best mid-range DSLR

Best mirrorless compact system camera

But if you're sure full format is the way you want to go, here are a few features to look out for:

Megapixels: Most full-frame DSLRs have around 20 million pixels – about the same as APS-C DSLRs, interestingly, and chosen as a compromise between resolution and overall image quality. At the top end, though, manufacturers tend to choose speed or resolution – the Nikon D4s has just 16 million pixels but shoots at 11fps, while the D810 has 36 megapixels and shoots at 5fps.

Construction: Cheaper full frame DSLRs are built to a high standard, but the pro models are built around a metal chassis and designed to survive heavy professional use over a long period of time. The D4s has a rated shutter life of 400,000 shots.

Continuous shooting speed: If you need to capture sports and action, and to shoot in really low light, you need the Canon EOS-1D X or Nikon D4s, end of story.

AF system: The cheapest cameras in this group use AF systems from the amateur DSLR market – they're perfectly adequate for relatively static or slow-moving subjects, but for action photography you're better off with the Nikon 51-point AF or Canon's 61-point AF systems, found in the more advanced models

Lens choice: When you invest in a full frame camera you're also investing in the lens and accessory system behind it. Canon and Nikon are in the lead here, and while Sony is ramping up its full frame system, most of the effort is going into its A7 compact system camera range. There are some good lenses for the Sony Alpha A99, but its future is unclear.

Nikon D810

Best full-frame DSLR: Nikon D810

Nikon D810 review

The Nikon D800's 36.3Mp sensor caused a big stir when it was released in 2012, offering the highest resolution of any Nikon SLR to date. While this enables superbly detailed images, you'll need to make sure your focusing skills (and lenses) can keep up, as any lack of sharpness is more obvious.

Nikon has since replaced the D800 with the D810, which keeps the same resolution but removes the anti-aliasing effect from the filter in front of the sensor (the earlier D800E offered a reduction in anti-aliasing rather than full removal).

The D810 brings a number of improvements over the D800, including a higher resolution display, faster continuous shooting (5fps vs 4fps), 33% longer battery life and Picture Control 2.0 image effects, which now include a Clarity micro-contrast adjustment and a Flat mode for maximum dynamic range – especially useful for video.

The D810 has a 51 point AF system compared to the 61 point system in the Canon 5D Mark III, but it copes admirably with tricky focussing situations. Indeed, both the AF and metering systems are identical to those in the Nikon D4s, but at a much lower price. Considering its massive resolution and advanced features, the D810 is reasonably light and the pop-up flash is a useful bonus.

Meet the rivals: full-frame DSLRs for enthusiasts

Canon EOS 6D

Canon 6D review

An excellent choice for the enthusiast and club photographer looking for a full-frame DSLR. These users will find that they have just about everything they need, and a bit more besides. Along with the Nikon D610, it's the cheapest full-frame DSLR on the market, and while it has a basic autofocus system and a modest continuous shooting speed, it delivers great image quality and the three-dimensional feel of the larger sensor size.

Nikon D610

Nikon D610 review

Nikon's hasty successor to the ill-fated D600 is actually a very good camera. Along with the Canon 6D, it's currently the cheapest way to get into full-frame photography, and offers good specifications for the money, including a 39-point AF system and 6fps continuous shooting. To a degree, the D610 is overshadowed by the newer D750 and its vari-angle screen, but the D610 is cheaper and produces the same level of image quality.

Sony Alpha A99

Sony Alpha a99

Sony A99 review

The first full-frame interchangeable lens camera with an electronic viewfinder (EVF), the a99 also features a versatile articulating rear screen. The camera is based on a 24.3Mp sensor that delivers plenty of resolution. The a99 performs well, though the AF system struggles to keep up with the competition and the selectable AF points are clustered around the centre of the frame. That's a shame, as the a99 has many virtues and useful extras.

Nikon D750

Nikon D750 review

Though it has the same pixel count as the D610, the D750 has better AF, metering and video systems as well as a wider sensitivity range, making it a more enticing option for dedicated enthusiast photographers. Some may have hoped for 8fps or faster shooting however. It also has a tilting screen, which is good, but a fully-articulating screen would be better. The D750 is a good choice for enthusiasts, but while the cheaper D610 is still around, that's a strong candidate too.

Nikon Df

Nikon Df review

The Df is styled to look like Nikon's classic FM-series 35mm film SLRs. It may not be the camera for everyone, but many enthusiasts will love the Df's retro styling and go-anywhere capability – and a few will love the fact that it doesn't shoot video! The Df uses the sensor from the Nikon D4s to deliver excellent low-light performance, though it doesn't match the D4s's continuous shooting speed. It looks wonderful, but the price seems high.

Meet the rivals: full-frame DSLRs for professionals

Canon EOS 5D Mark III

Canon 5D Mark III review

This is a perfect example of a pro-spec SLR that also appeals to serious amateurs. While the 5D Mark III is a very powerful camera, it weighs nearly 400g less than the 1DX. The 22.3MP sensor is outgunned by the 36.3MP Nikon D810, but it still delivers masses of detail. The 61-point AF system is terrific, with 41 cross-type sensors and five are dual cross-type. There's no built-in flash, unlike the D810, and it's a shame that the rear screen is fixed, but these are minor drawbacks.

Canon EOS 5DS

The 5DS won't be available until the middle of 2015, but the specifications and the pricing suggest that this camera could help Canon recapture the high-resolution pro DSLR market. It offers almost 40% more resolution than the Nikon D810 and externally it's identical to the existing EOS 5D Mark III – so it's easy to handle and much more compact than the heavyweight EOS-1D X. There will also be an 'R' variant with an additional filter to cancel out the anti-aliasing effect of the sensor, for even more detail.

Canon EOS-1D X

Canon EOS 1DX

Canon 1D X review

The 1DX is an amalgamation of the older Canon 1D and 1Ds models, blending their two specialities of speed and resolution. Speed is the real selling point, though – this camera boasts a 12 frames per second burst mode, which can be expanded to to 14fps in the Super High Speed Shooting Mode. The 18.1MP full frame sensor sounds a step backwards from the 21.1Mp chip inside the 1Ds Mark III, but Canon's chosen better image quality at higher ISO settings.

Nikon D4S

Nikon D4S review

This is a relatively minor upgrade from the fast, pro-spec D4, with improvements centring on better performance at higher ISO, which now stretches to 409,600 in expanded range, making this a real 'see in the dark' camera. As with Canon's 1DX, the D4S's pixel count is relatively low at 16.2Mp, but Nikon claims the lower pixel count reduces noise at very high ISO settings and enables a faster continuous shooting rate – and the D4S is built for speed.