Sony FE 28-70mm F3.5-5.6 OSS Review
Introduction
The Sony FE 28-70mm F3.5-5.6 OSS is the standard zoom kit lens for the Sony A7 full-frame E-mount compact system camera, and can also be purchased seperately. It features Optical SteadyShot image stabilisation, has nine elements in eight groups including three aspherical elements with one ED (Extra-low Dispersion) glass element, is dust- and moisture-resistant, and has a minimum focusing distance of 35cm with a maximum magnification of 0.19x. It has a near-circular 7 blade diaphragm which creates an attractive blur to the out-of-focus areas of the image, while an internal focusing mechanism means the lens barrel doesn’t move. The Sony FE 28-70mm F3.5-5.6 OSS lens is available for £449 / $499 in the UK and the US, respectively.
Ease of Use
The Sony FE 28-70mm F3.5-5.6 OSS lens mounted on a Sony A7R
Weighing in at 295grams, the plastic-bodied Sony FE 28-70mm F3.5-5.6 OSS is very light for a full-frame standard zoom lens. It's overall size complements a full-frame body like the Sony A7R body that we tested it with, as shown in the photos below. Note that the length of the lens hardly changes as you zoom from 28mm to 70mm.
The Sony FE 28-70mm F3.5-5.6 OSS lens mounted on a Sony A7R, set at 28mm
The Sony FE 28-70mm F3.5-5.6 OSS lens mounted on a Sony A7R, set at 70mm
The Sony FE 28-70mm F3.5-5.6 OSS lens mounted on a Sony A7R, set at 28mm
The Sony FE 28-70mm F3.5-5.6 OSS lens mounted on a Sony A7R, set at 70mm
Build quality is pretty good given the budget price-tag of what is after all a humble kit lens. The Sony FE 28-70mm F3.5-5.6 OSS has a sealed dust and moisture resistant design and is a natural partner for the A7 and A7R cameras.
Top of the Sony FE 28-70mm F3.5-5.6 OSS lens
Bottom of the Sony FE 28-70mm F3.5-5.6 OSS lens
The Sony FE 28-70mm F3.5-5.6 OSS lens boasts built-in Optical SteadyShot image stabilisation to help ensure clearer, sharper handheld shots. This is important as the A7 and A7R don't have a built-in image stabilisation system. In practice we found that the Sony FE 28-70mm F3.5-5.6 OSS reliably offered around 3-stops of compensation.
Side of the Sony FE 28-70mm F3.5-5.6 OSS lens
Side of the Sony FE 28-70mm F3.5-5.6 OSS lens
The wide and ridged zoom ring and the narrower manual focus ring are the only external controls of note. Manual focusing is possible via the textured focus ring when set on the specific camera body. The lens utilizes a linear motor to produce quiet and smooth focusing, making it well-suited to shooting video.
Front of the Sony FE 28-70mm F3.5-5.6 OSS lens
Front of the Sony FE 28-70mm F3.5-5.6 OSS lens
Rear of the Sony FE 28-70mm F3.5-5.6 OSS lens
The Sony FE 28-70mm F3.5-5.6 OSS lens has a metal lens mount. It accepts 55mm filters via plastic threads.
Side of the Sony FE 28-70mm F3.5-5.6 OSS lens in-hand
Side of the Sony FE 28-70mm F3.5-5.6 OSS lens
The Sony FE 28-70mm F3.5-5.6 OSS lens is commendably supplied with both a soft case and a fairly good quality plastic petal-shaped lens hood.
The Sony FE 28-70mm F3.5-5.6 OSS lens in-hand
The Sony FE 28-70mm F3.5-5.6 OSS lens with the ALC-SH132 lens hood fitted
Focal Range
At the 28mm focal length the angle of view is 54 degrees.
Field of view at 28mm
At the 70mm focal length the angle of view is 23 degrees.
Field of view at 70mm
Focusing
The Sony FE 28-70mm F3.5-5.6 OSS lens has quite a wide focus ring. There are no hard stops at either end of the range, making it a little more difficult to set focus at infinity. Polariser users should be pleased that the 55mm filter thread doesn't rotate on focus.
When it comes to auto-focusing, the Sony FE 28-70mm F3.5-5.6 OSS zoom is a quiet and fairly quick performer in good light on the Sony A7R that we tested it with, taking about 0.25 seconds to lock onto the subject.We didn't experience much "hunting" either, with the lens accurately focusing almost all of the time. In low-light, though, things aren't so rosy, taking much longer to focus and sometimes not even focusing successfully at all. The Sony FE 28-70mm F3.5-5.6 OSS is a quiet performer thanks to the linear motor driven internal focusing, making it ideal for movie shooting.
Chromatic Aberrations
Chromatic aberrations, typically seen as blue or purple fringes along contrasty edges, were apparent in quite a lot of our test shots, especially in high contrast areas. The examples below show the worst-case scenario.
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Light Fall-off and Distortion
With the lens set to its maximum aperture, there is very obvious light fall-off in the corners, requiring you to stop down by at least 3 f-stops to prevent it.
There's quite a lot of barrel distortion evident at 28mm in the RAW files - the Sony A7/A7R automatically and successfully apply corrections to the JPG files. At 70mm there's some pin-cushioning in the RAW files, which is again corrected when shooting JPGs.
Light fall-off at 28mm, JPG
Light fall-off at 28mm, RAW
Light fall-off at 70mm, JPG
Light fall-off at 70mm, RAW
Macro
The Sony FE 28-70mm F3.5-5.6 OSS isn't claimed to be a macro lens, offering a minimum focusing distance of 30cm at 28mm and 45cm at 70mm, with a maximum magnification of 0.19x. The following example demonstrates how close you can get to your subject at 70mm, in this case a Compact Flash memory card.
Close-up performance
Bokeh
Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc. In the FE 28-70mm F3.5-5.6 OSS lens, Sony employed an iris diaphragm with seven rounded blades, which has resulted in quite appealing bokeh in our view. We do realise, however, that bokeh evaluation is subjective, so we've included several 100% crops for your perusal.
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Sharpness
In order to show you how sharp this lens is, we are providing 100% crops on the following page.