Olympus M.Zuiko Digital ED 7-14mm f/2.8 PRO Review

This ultra-wide angle zoom lens for Micro Four Thirds (MFT) system cameras provides an angle of view equivalent to a 14-28mm lens used on a 35mm format and sports a constant f/2.8 maximum aperture throughout the zoom range. The lens is also dust and splash proof and is available from around £1000 at the time of writing. In this review we’ll take a look at how it performs.

The lens barrel is constructed from high quality, robust materials with a glossy finish and the bayonet is metal with a rubber gasket to prevent the ingress of dust and moisture into the camera body. Despite the robust construction and constant f/2.8 aperture the lens only weighs 534g. This makes the lens an ideal companion for the Panasonic Lumix G6 body used for testing.

Focusing is performed internally, although due to the bulbous front element, necessary to provide such a wide field of view there is no filter thread. Sliding back the focus ring reveals a distance scale and automatically changes the camera to manual focus mode, which is ideal for applying quick adjustments. However, it is quite easy to nudge this by accident when changing lenses, so care needs to be taken to ensure the lens is in the correct mode for shooting. The minimum focus distance is 20cm throughout the zoom range, which is ideal for close ups, or shooting in claustrophobic environments.

At 12mm sharpness is already outstanding in the centre of the frame and excellent towards the edges. The performance of the lens at this focal length is limited by diffraction, so there is nothing to be gained in sharpness by stopping down.

Zooming to 10mm results in a slight reduction in sharpness at maximum aperture, although performance is still excellent across the frame at maximum aperture. Stopping down to f/4 results in outstanding sharpness in the centre of the frame and excellent clarity towards the edges.

Finally, at 14mm sharpness is very good in the centre and good towards the edges of the frame at maximum aperture. Stopping down to between f/4 and f/5.6 results in excellent clarity in the centre and very good performance towards the edges for this focal length.

Chromatic aberrations are extremely well controlled throughout most of the zoom range for this kind of lens. Fringing barely exceeds half a pixel width, which should make these chromatic aberrations difficult to spot.

Falloff of illumination towards the corners is also well controlled. At 7mm and f/2.8 the comers are 1.52 stops darker than the centre of the image and at 14mm the corners are only 1.27 stops darker than the image centre. Stopping down to f/5.6 results in visually uniform illumination across the frame throughout the zoom range.

Distortion is well corrected in camera, but without corrections applied, detected 1.73% barrel distortion at 7mm which reduces to 0.61% at 14mm. The distortion pattern is uniform across the frame throughout the zoom range, which should make applying corrections in image editing software afterwards fairly straightforward.

A petal-shaped hood is built onto the front of the lens, which does a reasonable job of shading the lens from extraneous light that may cause issues with loss of contrast or flare. Strong sources of light in the frame, such as the sun can cause flare and a noticeable loss of contrast.

Currently, this lens is available for around £1000, which is good value for a lens of this quality. There is no direct equivalent currently available for Micro Four Thirds cameras, with the closest alternative being Panasonic’s 7-14mm f/4 lens, which costs around £800.

Given the ‘Pro’ moniker assigned to this lens, expectations of its build and performance should be high. During testing this lens proved itself worthy, by delivering images with outstanding sharpness, whilst handling well and sporting a robust dust and moisture resistant construction. The lens may be a little prone to flare, but given the extreme angle of view on offer and the compact size of the lens, this flaw may be something many will be able to forgive, or even forget.

Outstanding sharpness from maximum apertureRelatively compact and lightweightRobust buildDust and splash proofQuick access for manual focusGood valueExcellent control of CA

The blue column represents readings from the centre of the picture frame at the various apertures and the green is from the edges. Averaging them out gives the red weighted column.

Chromatic aberration is the lens’ inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software.