
Introduction
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional is a compact, light-weight and weather-sealed ultra-wide-angle to straightforward zoom lens for the Micro 4 Thirds system.
That includes a 35mm equal focal vary of 16-50mm, the Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional presents a relentless most aperture of f/4 all through its zoom vary, plus quick and quiet auto focusing.
It has an optical formulation comprised of 16 parts organized in 10 teams, together with one DSA (Twin Tremendous Aspherical) aspect, one ED (extra-low dispersion) aspect, two aspherical ED parts, one Tremendous ED aspect, one HR (high-refractive index) aspect, one Tremendous HR aspect, and one HD aspect.
Different highlights embrace a minimal focusing distance of 23cm and a most magnification of 0.21x, with a ZERO (Zuiko Further-low Reflection Optical) coating to regulate aberrations, ghosting and flare and a Fluorine coating to guard towards mud, water droplets, grease, and grime.
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional lens is offered now priced at £899.99 within the UK and $1099 within the US. The 8-25mm F4 is manufactured in Vietnam.
Ease of Use
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional is a weather-sealed wide-angle zoom lens with a devoted Micro 4 Thirds mount that’s manufactured from steel, with a rubber seal across the mount. Communication between lens and digicam physique is supplied by way of eleven electrical contacts.
Be aware nevertheless that with the intention to take full benefit of the weatherproofing, you will want to mount it on a equally weather-sealed physique, like the brand new flagship OM System OM-1 digicam that we examined it with.

Tipping the scales at 411g and measuring 88.5mm in size and 77mm in diameter, the Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional is a compact and light-weight ultra-wide-angle to straightforward zoom lens.
When it is unlocked and zoomed out to 8mm, although, it does achieve one other 3cm in size. It is truly a bit of shorter in size when set to 25mm than at 8mm.
The OM System OM-1 used for this take a look at is an excellent match for the lens, providing good steadiness, quick auto focus, and full environmental seals.


The M.Zuiko Digital ED 8-25mm F4.0 Professional lens could be very nicely constructed, totally residing as much as the PRO designation that Olympus have given it.
By way of options, the M.Zuiko Digital ED 8-25mm F4.0 Professional supplies a lot of the similar controls provided by a few of the larger, sooner Olympus Professional lenses.


As with all Olympus M.Zuiko lenses, the 8-25mm F4.0 Professional doesn’t provide picture stabilisation. As a substitute that is supplied by the digicam physique, on this occasion the frankly wonderful 5-axis system within the OM-1, which supplies 7 stops of compensation when paired with this lens.
So whereas the shortage of in-lens picture stabilisation is a non-issue for Olympus digicam customers, house owners of different producers merchandise who do not provide in-camera picture stabilisation in a few of their cameras, like Panasonic, could wish to contemplate a special lens.


With the 8-25mm lens hooked up to an OM-1 physique, focusing proved to be very fast in most conditions. This mix is able to locking give attention to a topic nearly immediately, even when alternating between shut and faraway topics.
In excessive low-light conditions chances are you’ll expertise a bit of focus searching on the lengthy finish, the place a lens with a sooner f/2.8 fixed aperture would assist keep away from this.



Handbook focusing is finished in a conventional trend, with the adequately sized focus ring mechanically coupled to the shifting lens parts, though there are not any onerous stops at both finish. Focusing is totally inner and the filter thread doesn’t rotate on focus.
There’s a reasonably sized focusing ring across the lens, which you should utilize when manually focusing the lens. You’ll be able to snap again the focusing ring to alter from auto focus to guide focus in an especially fast movement, snapping it again once more if you wish to change again to utilizing autofocus. When within the guide focus place, you will see a number of focal distances are displayed in each meters and ft.



Just under the zoom ring on the base of the lens is a operate button, marked L-Fn, which will be customised through the digicam’s important menu to regulate a lot of totally different actions. One helpful operate is depth of discipline preview – this lets you see how your picture will have a look at the chosen should you maintain down the L-Fn button, and is especially helpful when working with slim apertures.
The Olympus M.ZUIKO Digital ED 12-45mm f/3.5-6.3 EZ lens encompasses a 72mm filter thread and a entrance bayonet for attaching the equipped LH‑76E petal-shaped lens hood, which twists into place to lock and launch it from the lens. The filter thread doesn’t rotate on focus, which is nice information for anybody intending to make use of a polariser or ND grads.






Focal Vary
The 8mm focal size supplies an angle of view of 107 levels.

8mm
The 25mm focal size supplies an angle of view of 47 levels.

25mm
Chromatic Aberrations
Chromatic aberrations, sometimes seen as purple or blue fringes alongside contrasty edges, will not be an excessive amount of of an issue with the Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional lens, besides in areas of very excessive distinction.

8mm

25mm
Vignetting
With the lens set to its most aperture of f/4, there’s some gentle fall-off within the corners, requiring you to cease down by no less than 2 f-stops to fully forestall it.

8mm

25mm
Distortion
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional does not exhibit an excessive amount of barrel or pincushion distortion, as you possibly can see within the images beneath.

8mm

25mm
Sunstars and Flare
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional is able to producing good sunstars when stopped-down to f/22, as proven beneath, though the lens is inclined to flare when taking pictures straight into the solar, even with the equipped lens hood fitted.

8mm

25mm
Macro
The Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional is just not actually a macro lens, but it surely does provide a usefully shut focus level of 23cm / 9.05in throughout your entire zoom vary from the sensor aircraft and a most magnification of 0.21x.






Bokeh
Bokeh is a phrase used for the out-of-focus areas of {a photograph}, and is normally described in qualitative phrases, reminiscent of easy / creamy / harsh and so forth.
Olympus have paid shut consideration to this facet of lens use, using a 7-segment diaphragm with rounded blades for pretty pleasing bokeh.
In our view, their efforts have been fairly profitable for an ultra-wide to straightforward zoom lens – see the examples beneath to guage for your self.










Sharpness
With the intention to present you ways sharp the Olympus M.Zuiko Digital ED 8-25mm F4.0 Professional lens is, we’re offering 100% crops on the next pages.