The idea behind the 4/3 system has been reminded several times already, but it would be difficult not to mention it if you are going to perform a test of such a lens as the Olympus Zuiko Digital ED 14-35 mm f/2.0 SWD. Let’s refresh our memory once again. If you are being weary of it, though, feel free to skip this section and go to next chapters.
The usage of a sensor which is two times smaller than a 35-mm film frame was not without reasons. Malicious people might say that the first and main reason was the inability to produce a bigger detector by Panasonic but it is only partially true. Olympus decided to base its whole system on this small sensor and they did it after thinking the whole thing through time and again. A smaller detector means not only disadvantages, connected with the smaller size of the pixels, but also advantages of better optics. Appropriately designed lenses can be physically lighter and smaller than their full frame equivalents and optically better at the same time. If the weight and dimensions remain at the same level, the 4/3 system can still offer better parameters. A perfect example of such instrument is exactly the Olympus Zuiko Digital ED 14-35 MM F/2.0 SWD. It gives us the same fields of view as full frame 28-70 mm classics but at the same time if offers f/2.0 aperture so by 1 EV better than the best rival devices. To be completely honest we must say that there are two facts to Olympus’s disadvantage, though. Firstly, contemporary journalistic zooms of this class start from 24 mm focal length so they can give you a wider field of view by as much as 9 degrees; secondly, the depth of field, reached by f/2.8, is still smaller than in the case of the Olympus at f/2.0
Dry comparison of facts is not enough, though. Optical properties are also important – in most of cases they are the 4/3 system lenses’ significant advantage. Will it be the same for the Olympus 14-35 mm? How will it fare compared to full frame competitors? We hope the following chapters will be able to answer that.
2. Pictures and parameters
|Construction:||17 groups / 18 elements|
|Field of view:||75–34 deg.|
|Min. focusing dist.:||0.35 m|
|Filter size:||77 mm|
|Dimensions (length x diameter):||123.0 mm × 86.0 mm|
3. Build quality
At the beginning, let’s compare the Olympus, tested here, with full frame lenses of similar angles of view and f/2.8 aperture. The following chart presents such a comparision well. As you see, despite the best fastness, the Olympus is not the heaviest instrument there. It’s true that it remains the longest but the difference between it and the competitors is not so big.
When the better fastness of the Olympus is opposed to the wider focal range, we can try to compare it with the 24-70 mm f/2.8 class devices. The next chart will allow us to look more closely at the Olympus’s parameters and those of its rivals. Once again the dimensions and the weight of the Olympus are nothing exceptional – it doesn’t differ almost at all from the Canon and the Nikkor; only the lightweight and compact Sigma sticks out here.
How big the Olympus 14-35 mm really is can be seen in the photo below, where that model is positioned near the Olympus 35-100 f/2.0 and the Sigma 1.4/30.
The build quality and the design of the tested lens are beyond reproach. It is made very well, as it befits a high-end instrument – we have here a solid, weather-sealed construction with a metal mount and a non-rotating filter thread, 77 mm in diameter, which surrounds a huge front element with a diameter of 7 cm.
It’s worth adding that the lens changes its dimensions with the change of focal length. It is the shortest near 20 mm; on passing to 14 mm the front element extends by 7 mm and at 35 mm – by 17 mm. You change the focal length by using a comfortable, big and ribbed ring. It moves smoothly and is well-damped. In fact the change of dimensions is the only thing which could make us worried because it might undermine the tightness of the tested lens. Here, however, we count on the opinions of our Readers, the users of this device – they can tell you about it much more than we can.
The second big ring which you can find on the barrel is for manual focusing. It is an example of a rare solution in Olympus lenses – the ring is completely mechanical and that’s why it moves the distance scale even when the body is switched off or the lens detached. The ring allows us to set the focus with utmost precision. Running through the scale will take a 200-degree turn.
Between these two big rings you can find a clear distance scale, expressed in meters and feet, behind a glass window.
The optical construction of the lens consists of 18 elements in 17 groups. Among them you can find two low-dispersion ED glass elements, one aspherical element, and one which combines those two properties – it is made of low-dispersion glass and was produced in the “glass mold” technology, incorporating an aspherical metal die at the same time. Inside, there is also an aperture with nine diaphragm blades which can be closed down to f/22.
The buyer gets both caps, a petal-type lens hood and a case included in box.
4. Image resolution
The resolution of the tested lens was based on the strength of RAW files from the Olympus E-3 camera. Its sensor features 10 million of photosensitive cells which ensure high linear density of pixels and high MTF values – comparable to those we get in tests based on the Canon 50D. It’s worth remembering that the best prime lenses, tested on the E-3, can reach results as high as 51-52 lpmm and the decency level in this case is near 34-35 lpmm.
Let’s look how the Zuiko Digital ED 14-35 mm f/2.0 SWD performs in the frame centre.
Well, well. Only one word comes to mind here – impressive. The performance of the lens is perfectly even – the differences between particular focal lengths are very small. What’s more, by f/4.0 at all focal lengths we reach results near 51 lpmm. Practically no system fixed focal length lens can fare better. At the maximum relative aperture the Olympus lens performs very well too. The MTFs we get there are in the range from 43 to 47 lpmm so the images are sharp indeed. Only the best lens of 24–70 mm f/2.8 class which have been tested by us, namely the Sony Carl Zeiss Vario Sonnar 24–70 mm f/2.8 T* SSM, can compete with the Olympus here. It also showed a very even performance and at the maximum aperture gave us images with equally great sharpness. The Nikkor AF-S 24–70 mm f/2.8G ED and the Sigma 24–70 mm f/2.8 EX DG HSM fare a bit worse here and the Canon EF 24–70 mm f/2.8L USM lags behind the most, as at the maximum aperture it barely brushed against the decency level. The Canon is the oldest lens in this group, though, and supposedly the first to be replaced by a newer model.
What does the edge of the frame look like? Let’s have a glance at the graph below.
The word „impressive” still describes perfectly the performance we see here. Even at the maximum relative aperture the MTFs reach nearly 40 lpmm, exceeding safely the decency level. On slight stopping down the MTFs increase to levels which would be very hard to criticize. The lost of that evenness of performance at all focal lengths is one thing that can be regretted here- it becomes especially visible in the frame centre. Now, we can notice that 14 mm focal length is significantly better than the 23-35 mm range. Such a problem is not serious at all, though. Especially that the Olympus compares so well with its full frame competitors. To make this comparison completely fair we should take into account the results of other full frame lenses at the edge of full frame. There, at the maximum aperture, few devices exceed the decency level. Some of them don’t manage it even on stopping down by 1 EV. The advantage of the Olympus is clear and indisputable then.
At the end we would like to present our test chart crops, saved in JPEG format along with the RAW files, which were used to determine the MTF50 values.
5. Chromatic aberration
The graph below shows the relationship between the chromatic aberration and the value of the aperture for three focal lengths: 14, 23 and 35 mm.
It would be difficult to complain about anything here. Only the difficult combination of the maximum relative aperture and the shortest focal length gives us the medium level of aberration. In all other cases the aberration remains low or very low. The tested lens once again deserves our praise.
In the case of the 4/3 system the distortion is always an interesting issue. A small sensor demands using very short focal lengths and it might always be a potential source of problems with the correction of that aberration. How does the Olympus Zuiko Digital ED 14–35 mm f/2.0 SWD fare here? At the shortest focal length we noticed barrel distortion of –2.52%. This value is noticeable but not especially bothersome. In the middle of the range the distortion decreases to –0.41% and to –0.01% at the maximum focal length. The Olympus shouldn’t be ashamed of such a performance, especially compared to its full frame competitors. In fact the only difference is the sign of the distortion. For the Olympus it is barrel in the whole focal lengths range . For the lenses of 24-70 or 28-70 mm class we deal with barrel distortion at the wide end which becomes quickly zero with the increase of the focal length and is pincushion for the middle and the end of the range.
|Olympus E-3, 14 mm|
|Olympus E-3, 24 mm|
|Olympus E-3, 35 mm|
7. Coma and astigmatism
The coma makes itself felt especially at the shortest focal lengths. It is quite clearly visible in the 14-23 mm range and it decreases significantly at 35 mm. Perhaps it doesn’t reach a huge or high level but it can be described as a bit above medium. In other words, it could have been a bit better.
Astigmatism won’t cause us any problems for a change. The average difference between horizontal and vertical MTF50 values amounted to 4% which is a very low result. When you analyze the astigmatism results for particular focal lengths, the differences will be slight but you can still notice that the level of this aberration in the middle of the focal lengths range is a bit higher than at both ends.
The next interesting category in the case of the 4/3 system is vignetting. Usually 4/3 lenses outclass here any full frame competition. Let’s remind here that, for example, the Sigma 24-70 mm f/2.8 on full frame could lose as much as 50% of light in the frame corners. Now, have a look at the performance of the Olympus 14-35 mm.
Despite dealing here with the excellent f/2.0 fastness, at the shortest focal length the vignetting reaches 31% (-1.07 EV). It is a noticeable value but, taking into account the angle of view we get here and the aperture, this result can’t be criticized. Especially that after using f/2.8, the vignetting decreases to 16% and by f/4.0 it is as low as 10% – a truly imperceptible level.
In the middle of the focal lengths range the vignetting won’t be bothersome at all. At the maximum aperture it amounts to 17% (-0.53 EV) and it decreases to only 8% on stopping down the lens to f/2.8.
The light fall-off in the frame corners increases slightly at the maximum aperture but also there it is not especially bothersome. By f/2.0 the vignetting is 25% (-0.85 EV) and it decreases to an imperceptible value of 10% by f/2.8.
9. Ghosting, flares and transmission
Let’s start with describing the transmission graph of the tested lens, which is presented below.
If you deal with one of the most advanced lenses in the E system you should expect the best performance in every category. The transmission doesn’t impress though. It’s true that we see a quite flat graph in the range from 450 to 670 nm, which ensures the right colour rendition. The problem is that the maximum transmission, in this case for red light, reaches the level of 84-85 % which can be considered medium only. It’s enough to remind here that full frame equivalents of the tested lens with the parameters of 24-70 mm f/2.8, produced by such companies as Sigma or Nikon, feature transmission level of 90-94%. Compared with it, the result of the Olympus is simply weak…
There’s one thing which should be taken into account, though. The tested lens consists of as many as 17 groups of elements so there are 34 air-to-glass surfaces to cover. It can be easily calculated that, in order to get the 84-85% transmission level, on one surface we lose about 0.5% of light. Such a result looks a bit better but still keep in mind that the best coatings used in photography optics can reach the level of 0.2-0.3% of loss on one air-to-glass surface. We should expect such coatings in the case of the best and the most expensive lenses from any producer. Unfortunately Olympus failed to deliver here.
The loss of as much as 15% of light in the red part of the spectrum, 18-19% in the middle of the range and over 20% in the blue part must have a negative effect on the work against bright light. As you can notice in the pictures below, it does. It’s worth adding here that the flares are a bit less bothersome at the maximum aperture and a bit more so when we stop the lens down.
It is evident there is an SWD motor in the tested lens. The focusing mechanism is simply noiseless and is as quick as a flash. Running through the whole scale, no matter from what end, takes about 0.5 of a second – a splendid result indeed.
Accuracy is a small problem, though. A high-end system lens, put on the E-3, also undeniably the best body in the system, should be practically 100% accurate. In reality, that set in our studio missed in 9% of shots. It is not a lot but we had expected a better result, especially that the tested lens on the body belonging to our editorial office, also had a slight tendency to front focus.
- very solid, weather-sealed casing,
- sensational image quality in the frame centre at all focal lengths to boot,
- very good image quality at the frame edge,
- well-corrected chromatic aberration,
- not very bothersome distortion,
- low astigmatism,
- not many problems with vignetting,
- silent and quick autofocus.
- weak transmission for this class of equipment,
- average work against bright light,
- high price.
Taking up photography seriously is, unfortunately, also seriously expensive. If we have chosen the 4/3 system, decided to buy a good body and we want to own a high-end, fast, journalistic zoom lens, Olympus offers us such a device. The fact that the price is rather high might be quite understood in a way. Fast journalistic zooms are always expensive, no matter what system you take because there’s simply no compromise possible in their construction. The problem with the Olympus is that this device is the most pricey of all this class instruments without giving you such a wide angle of view as full frame lenses with focal lengths ranges starting from 24 mm.
Do we get something in return? Of course we do. We get f/2.0 aperture – although it can’t give us such a depth of field as full frame, it can easily compete with any APS-C/DX sensor. What’s more, the fastness better by 1 EV means the possibility of using speeds by 1 EV lower. You must add the image quality at the edge of the frame – in this area full frame lenses can’t compete with the Olympus at all. One more advantage, which neither Canon, nor Nikon, nor Sigma can offer: the Olympus 14-35 mm on the E-3 body is a set with the image stabilization as efficient as 3 EV (or so show our tests). Here only Sony and its Zeiss 24-70 mm can compete with the Olympus, although in the case of the A900 and the A850 the stabilization was nowhere near as efficient. If we start comparing prices, though, it turns out that the E-3 plus the 14-35 mm set will be cheaper than the A850/A900 and the Zeiss 24-70 mm.
One more comparison which we can present here. The E-3 plus the 14–35 mm can give us the angles of view range, the depth of field and the quality of work more or less the same as, e.g. the Canon EOS 7D with the EF-S 17–55 m f/2.8 IS USM. Here the duel is fierce indeed because the Canon set features efficient stabilization and an USM motor, the 7D itself being a good journalistic camera. What’s more, the Canon equipment is by some several hundred dollars cheaper than that of Olympus. Similar set can be constructed using Nikon devices – the D300s camera and the Nikkor 17-55 mm f/2.8. We will lack stabilization here, though and the price is higher than in the case of the Canon (but still lower than the price of the Olympus). Pentax can also take part in the competition. The K-7, small but solidly build, is a huge advantage and the 16-50 mm f/2.8 Pentax lens, although optically worse than the Olympus, will give you the widest angle of view of all sets, described in this paragraph. The Pentax, contrary to the Nikon, features stabilization. It is not as efficient as in the E-3 but still it offers 2 EV. The price of the Pentax set, the lowest of all, is the additional strong point – you can have it for about 1900 $. Only Sony has left this segment lately. The A700 model has been withdrawn from the market long time ago and the line-up of this company still lacks a good 17-55 mm or 16-50 mm class f/2.8 lens.
Whew…I must admit if anybody presented all these sets, mentioned above, before me and asked me to choose one of them I would face a serious problem. On the other hand such problems are nothing but sheer pleasure. Rich choice and fierce competition have always been and will be a very good thing for customers.