Sony a850 Review

Body only: £2,000 (Guide) / £1,600 (Street)
 IMAGE sensor: Exmor CMOS full-frame
 IMAGE RESOLUTION: 24.6-megapixels
 LCD: 3in (921,600 dots)
 STORAGE: CompactFlash & Memory Stick Pro
 WEIGHT: 850g (without battery and card)
 PHONE: 08705 111999
 WEBSITE: www.sony.co.uk

For the majority of enthusiasts, as capable as advanced-amateur DSLRs like the Nikon D300s or Canon EOS 7D are, the lack of a full-frame sensor (in other words one the same size as a 35mm film frame as opposed to the smaller APS-C type) is the major factor holding them off buying one. Although originally only found in expensive pro models, a wave of more 'affordable' full-frame DSLRs over the last couple of years or so has brought the benefits of full-frame photography to a wider market, with the likes of the Nikon D700, Sony Alpha 900 and Canon EOS 5D all proving very popular. The Alpha 850 is Sony's second full-frame DSLR and is pitched attractively below £2,000, where the majority of DSLRs have APS-C sensors.

Handling & ease of use
As with all DSLRs sporting a full-frame sensor, the Alpha 850 is larger, sturdier and heavier than the majority of consumer DSLRs. With its target audience ranging from enthusiasts through to professionals, the build quality and size of this Sony does away with lightweight polycarbonate in favour of an aluminium chassis and magnesium-alloy body shell. The larger sensor demands a larger mirror box chamber and viewfinder prism, hence the increase in dimensions of the body and pentaprism compared to amateur models.
The body shape split opinion within the magazine team, with some liking the large top-plate and others feeling it looks dated, so judge that for yourself! One benefit of the larger body is that the control buttons are larger than average and spaced out more. This means in theory that ease of use is improved, although it has to be said that there are lots of buttons located on the top and also on the back of the A850. Thankfully, they are clearly marked and the majority only handle one function, so it's not a difficult camera to get to grips with, especially if you have previous experience using DSLRs.
The viewfinder on the Alpha 900 is arguably the best found on any digital SLR and the Alpha 850 is not far behind – it's extremely bright and sharp and a world away from what you find on DSLRs with APS-C sensors. As well as dioptre correction, it also features an eyepiece blind for when shooting with the eye away from the finder, as well as eye-start sensors to activate the display.
The 3in LCD monitor is excellent as its 921,600-dot screen delivers a bright, crisp display. The menu system is very good too, with various options allowing you to access major functions in different ways to suit your preferences. 22/25

Features
The primary reason for buying the Alpha 850 is its 24.6-megapixel CMOS Exmor sensor, which delivers 36MB Raw files with a resolution of 6048x4032 pixels that allows for large, detailed prints of A3 and above. Processing is handled by dual BIONZ image processors, which is the same system as used on the A900, although the slightly slower frame rate of 3fps means they've less data transfer during continuous shooting.
The Sony A850 has nine user-definable AF points but there are also ten 'assist' points that aid AF when shooting with the system set to multi-point. A switch located bottom left of the body's lens throat allows you to set the AF mode to Single, Continuous or Auto-AF mode, as well as manual focus. The A850 also sports an AF illuminator (located on the front next to the A850 insignia), which produces a red beam to aid the autofocus lock on subjects in low light.
The main exposure dial on the left of the top-plate reveals that subject-biased scene modes are not on offer on the A850. However, as well as the core four modes (program, aperture- and shutter-priority and manual) there is a green full-auto mode for fuss-free shooting, as well as three custom modes that allow you to set up the camera's key functions for your preferences.
The exposure system is well catered for with a choice of 40-segment Honeycomb metering, spot and centre-weighted average patterns, selected by a well-positioned thick flick-switch on the camera's rear beside the viewfinder. As you'd expect of such a high-end model, there are various options to apply overrides, including exposure compensation for ambient and flash exposures, Auto-Exposure Lock and auto-bracketing. You also have the option of D-Range Optimizer, which can be used when shooting high-contrast scenes (such as contre-jour), to improve highlight and shadow detail. You can tweak image characteristics further by choosing a Creative Style (e.g. Vivid, Portrait etc) or by bracketing the White Balance settings.
As with other Alpha models, the A850 sports body-integral image stabilisation in the form of SteadyShot Inside. Along with the A900, it's the only full-frame DSLR to boast this facility, which is claimed to give a 2.5 to four-stop benefit.
Summarising the other key features, there's an anti-dust system present on the A850, shaking the sensor when you switch the camera on and off, while the ISO range is a useful 200-3200 (plus Auto), with the option to extend it down to ISO 100 or uprate it to 6400. While DT lenses are designed for APS-C sensors only, they can be attached to the A850, which then automatically crops to shoot 11-megapixel APS-C images, with crop lines on the viewfinder providing a guide for composition.
Finally, it's worth pointing out two features not found on the A850, namely HD video and Live View. While the former is not yet an established function, Live View is a facility we'd expect to see on all but the most budget of DSLRs. Overall though, you can't really quibble with what's on offer for the price. 23/25
Performance
The Sony proves to be a very accomplished performer and is certainly good enough to be used for professional as well as recreational use. It's fast in operation, with no notable lags, unless you're blitzing through long sequences of RAW+JPEG files. The autofocus system is fast and accurate but not as quiet as Canon or Nikon lenses. The Honeycomb meter is consistent, delivering good exposures, although scenes with sky do tend to result in slight underexposure, so regularly check your histogram/review screen. The Auto White Balance works well, but like most, struggles with tungsten scenes, producing images with a warm cast. We used the A850 mostly with the 28-75mm f/2.8 SAM lens and images showed very good detail and good contrast. Colour reproduction is accurate with good saturation. Noise is handled better than on the A900 and is evident from ISO 800 upwards and at higher ISOs is only slightly more prominent than with the Canon and Sony. Overall, the Alpha 850 proves to be a very good all-round performer. 22/25

Verdict
The Alpha 850 is an oddity in the sense that it is virtually identical to the A900. But as we've seen with its consumer models, Sony isn't afraid to release a number of similar cameras if it gains them market share. The fact is, the Alpha 850 is a very tempting proposition, especially when you can find it for £1,500 if you shop around. You'll also find the Canon EOS 5D MkII and Nikon D700 at similar prices, but the Sony still rules supreme when it comes to megapixel count. The differences between it and the A900 are so minor that its lower price point makes it far better value for money. In fact, in terms of VFM alone, it's is arguably the best option currently available, although the EOS 5D MkII, with the option of HD video, runs it very close indeed.

Handling & ease of use 22/25
Features 23/25
Performance 22/25
Value for Money 23/25

A850 & A900: 
What's the difference?
The A900 has a guide price of £2,100 compared with £1,850 for the A850. The main differences are the A850 fires at three frames-per-second (the A900 boasts 5fps) and boasts a 98% viewfinder (100% coverage on the A900). Oh, the A900 is supplied with a free remote control that you'll need to buy (£30) if you opt for the A850!


How the Sony A850 compares to rivals
Canon EOS 5D MkII 
In terms of handling, the Canon feels more refined and better balanced and is (only very slightly) easier to use. In terns of features, its resolution of 21.1 is lower than the Sony but it does boast HD video for the multimedia user. Other than that, in terms of camera features, they're very similar, but the Canon has the advantage of an extensive system of lenses and accessories. There is no discernable difference in image quality between the two.
Nikon D700 
The D700 is a beautiful tool that's easy to use and slick in operation. It boasts a wide range of features including a 51-point AF system and the highly-regarded 1005-pixel Matrix meter, along with an extensive system of lenses and accessories. Compared to the Sony and Canon, its resolution of 12.1-megapixels is low, although in use, image sharpness at large magnifications isn't that far behind and image noise at high ISOs is the best of the three.