The Sony 70-200mm F2.8 G is an impeccably-built lens, which matches its Canon and Nikon counterparts in its 'professional workhorse' level of quality. The barrel features solid metal construction, and the zoom and focus rings are extremely smooth in operation. However it's worth noting that the lens is not described as weather-sealed, and most notably there's no seal around the mount to prevent dust or moisture ingress at this vulnerable point.
Special mention must be made of the three AF stop buttons, which are positioned at 90 degree intervals around the barrel, perfectly placed for operation by your left thumb no matter which orientation you're holding the camera (portrait or landscape). If you use one of Sony's higher-end bodies, they can also be reassigned to depth of field preview if you prefer (or even to the somewhat less useful 'Intelligent Preview').
Unusually, the lens offers two modes for manual correction of autofocus (which Sony calls 'Direct Manual Focus'). In 'Standard' mode, the autofocus will override any movements of the manual focus ring when using either continuous autofocus (AF-C), or continuous advance in AF-A mode; this is useful to prevent accidental movements of the focus ring from affecting action shooting. In 'Full Time' mode, any movement of the manual focus ring will override AF.
On the camera
This is a relatively large and heavy lens, and therefore best matched to the more substantial bodies in Sony's range - essentially the Alphas 700, 850 and 900. It's also one which benefits from the use of a vertical grip, especially if you're likely to be shooting much in portrait format. But while sizeable lenses like this are never entirely at home on budget cameras, you'd really not want to mate this one with Sony's current budget range, as the handling is distinctly awkward due to the unusually-designed grip. To be fair, though, it's much better on the more conventional Alpha 450/500/550 triplets.
Potential upgraders should also be aware that this is a much bigger, heavier beast than typical consumer telezooms such the 70-300mm - it's relatively unlikely to be something you'd want to carry around with you all day at Disneyland (for example).
This lens features Sony's ultrasonic-type Super Sonic Wave Motor (SSM) for autofocus, which is essentially silent in operation and, in our experience, very accurate indeed. It's also pretty quick, and while it's perhaps not quite up to the same lightning-fast standard of Nikon's latest AF-S 70-200mm F2.8 VR II, this is unlikely to cause you to miss many shots.
However as always it must be noted that focus speed and accuracy is dependent upon a number of variables, including the camera body used, subject contrast, and light levels.
Lens body elements
The lens uses Sony's Alpha mount, which is identical to Minolta's A-type.
The gold contacts are used for communication with the camera, and the fact that their are 8 rather than 5 indicates that this is a 'D'-type lens. The black metal lever controls the aperture.
The filter thread is 77mm, which is the de facto standard for professional lenses, and shared with Sony's other F2.8 zooms. It does not rotate on autofocusing, which should please filter users.
The 10cm deep bayonet-mount SH0010 lens hood is excellent; it's solidly made of black plastic with a felt lining to minimize the reflection of stray light into the lens. It's even got a little window with a sliding cover to aid operation of a polarizing filer: in this picture it's shown at the top of the lens for visibility, but normally you'd place it underneath.
All in all, top marks (Nikon could learn something here).
The zoom ring rotates 90 degrees clockwise from 70mm to 200mm, with intermediate markings at 100mm and 135mm. The ribbed rubber grip is a generous 36mm in width, and the action is extremely smooth and precise.
In common with other 70-200mm F2.8 lenses, the zoom action is entirely internal.
The focus ring is 32mm wide, and rotates fully 190 degrees clockwise from infinity to 1.2m. It does not rotate during autofocus, and the Direct Manual Focus system allows override of the autofocus at any time.
Again focus is internal, and the action is smooth, precise and well-damped.
The distance scale lies between the zoom and focus rings, with extensive markings in both feet and meters. The focus ring travels slightly past the infinity mark, apparently to allow for the effects of ambient temperature variations.
Three switches on the side of the lens barrel control the autofocus. At the top is the auto/manual focus selector, and below it a smaller switch to set the Direct Manual Focus (DMF) mode (which you'd normally leave on standard). The bottom one allows you to limit the minimum focus to 3m, useful to reduce hunting when shooting sports.
The lens also has three AF-stop buttons, arranged at 90 degree intervals around the barrel just behind the focus ring such that one is always perfectly positioned for operation by the right thumb no matter which way round you hold the camera. On higher-end bodies these can be re-assigned to other functions, including depth of field preview.
The tripod mount design is rather similar to Canon's, in that it can only be removed when the lens is detached from the camera body (which can be slightly annoying). There are orientation marks at 90 degree intervals for both portrait and landscape shooting, and two tripod attachment threads, one the standard 1/4", and the other the somewhat less common 3/8".
Reported aperture vs focal length
This lens allows an aperture range from F2.8 to F32 at all focal lengths.