Zuiko Digital ED 90-250mm 1:2.8
When it comes to telephoto lenses, not much is happening. Since the advent of autofocus lenses, nobody but the Japanese companies make them. Besides, it's the wide angle lenses that present the real challenge to the DSLR manufacturers.All enthusiast cameras and most pro camera have smaller-than-film sensors, making the field of view narrower than on film cameras. The so-called crop factor is new both to the manufacturers and the customers, making it necessary to produce and sell new lenses. When it comes to original equipment manufacturers, most of them have a good telephoto lens line-up. Third party manufacturers, though, are not faring quite as well, with Sigma being the only significant contender.
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The lens is easy to use. Both the focus and the zoom ring are wide and well placed. |
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The lens is 276 mm long, with a maximum diameter of 124 mm and a weight of 3270 grams. |
Since it was only in 2003 that Olympus again became active in the SLR scene, they're the only company to have new telephoto lenses with 1:2.8 aperture. Since their 4/3 system is a bit different than the others, they can make lenses that are quite unlike those seen before. All Olympus 4/3 lenses have the same angle of view as the usual film lenses, but at half the focal length. This is because the 4/3 system is half the size (18 x 13.5 mm) of the full-frame film format (36 x 24 mm). This makes Olympus lenses somewhat unique, as they don't project a significantly larger image circle than the sensor itself.
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A tripod is essential with this kind of weight. |
The difference is that with most other digital cameras (except for full-frame beasts) and most lenses, except those that are specially made for crop cameras, a huge part of the image circle is unused. This means that a lot of glass is wasted, making the lenses heavier and larger (and more expensive, too) than necessary.Since Olympus started fresh, they have a certain competitive advantage. It's still too early to judge as to how the 4/3 system will perform in the future, though. At the beginning, each camera system has its teething problems. Sometimes, engineering can't produce the desired results, and sometimes, the technology to implement all the advantages of a forward-thinking system just isn't ready yet.
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The lens is built like a tank. It’s also protected against dust, moisture and rain. |
Some other Zuiko Digital lenses have already proven their advantages, particularly the 150 mm/2.0, the 300 mm/2.8 and the 50-200 mm/2.8-3.5. They're smaller and lighter than the competition – note that we're talking about viewing angles, not absolute focal lengths. Also, their aperture is larger than the competition's, compared to the viewing angle, size and weight. But it was the Zuiko Digital 35-100 mm/2.0 that showed how quickly the race for maximum aperture nullifies some of the promised system advantages. The 35-100 mm/2.0 was very much a disappointment. The 4/3 lenses were supposed to produce higher quality images at a larger aperture and smaller bulk than the competition. The 35-100 didn't do that.
However, this lens is something completely different. It’s as good as the 150 mm/2.0, 300 mm/2.8 and the 50-200 mm/2.8-3.5. And that’s saying something.
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Near the camera, there's the knob used to set the focusing distance. |
However, this lens doesn't deliver on the smaller, lighter lens promise. There's a Sigma lens, the 120-300 mm/2.8. On 1.6 crop cameras, it has a very similar viewing angle to the Zuiko Digital 90-250 mm/2.8. The equivalent viewing angle would be 198-480 mm, which is pretty much the same, at the same aperture. However, the Sigma lens is 5 mm shorter and 700 g (that's more than 1.5 pounds for those of you who haven't caught up with this whole metric thing yet). It’s also considerably cheaper. However, I haven't tested it yet, so I can't really say if it's as good optically.
The point I'm trying to get across is - the whole lighter, smaller lens thing doesn't really work here. However, Sigma is the only company to produce such a lens.
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The wide zooming ring makes it possible to adjust the focal length even when wearing thick gloves. |
Zuiko Digital ED 90-250 mm/2.8
Long telephoto lenses (less than 10 degree diagonal viewing angle) with large apertures are most popular amongst pros. However, the only ones that are really long and really good are primes. Telephoto zooms with a f/2.8 aperture are very much like avian dentures. In most cases, zoom lenses with 2.8 aperture stop at 200 mm (or 300 mm with the Sigma), giving a 35 mm equivalent of 300/320 mm (450/480 mm with the Sigma). However, Olympus, due to the smaller sensor they use, can produce a lens taht has a viewing angle of a 180-500 mm lens on a full frame camera, or an approximately 120-320 mm lens on a crop camera. (The variation is due to the fact that most camera makers use 1.5x crop factor sensors, while Canon uses 1.6 crop factor.) However, the Zuiko 90-250 mm has something more to offer. High image quality and the kind of aperture that used to be the domain of prime lenses.
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The tripod ring, easy to rotate into portrait or landscape orientation. |
My first disappointment with the Zuiko Digital 35-100 mm/2.0 was the fact that it was poorly balanced, with too much weight in the front. The 90-250 is a different beast entirely. Considering its angle of view, its size and weight is not a shock. Despite this, it handles better than the 35-100 mm/2.0 lens. That still doesn't make it handholdable, though – after all, it does weigh 3270 g. A monopod is practically a must.
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These buttons lock the current settings. |
The Zuiko Digital ED 90-250 mm/2.8 measures 276 mm in length, with a maximum diameter of 124 mm. It has 17 elements in 12 groups. Three of these lenses are special ED lenses, which contribute to decreased light dispersion. The smallest aperture is 22, while the minimum focusing distance is 2.5 m.
The lens is very easy to handle, aside from its weight. Near the mount, there's the focus distance limiter, which makes it possible to focus from 2.5 m to infinity, from 8 m to infinity or just between 2.5 and 8 m. This is a useful thing, as limiting the focal range means less travel for lens elements, making focusing faster. The large zoom ring functions very smoothly. If you're not using a tripod and the tripod ring bothers you, it's easy to turn it around. Near the top of the lens is the focus ring. As with all other Zuiko Digital lenses, it's a fly-by-wire thing, so there's no direct mechanical control. It doesn't take long to get used to it, though. At the topmost part of the lens, there are three buttons used to lock the focus. The lens takes filters, too, but with a whopping 105 mm diameter.
The lens is built like a tank. A proper one. It’s also protected against dust, moisture and rain.
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Monopod is a must. Despite taking pictures in sunlight, the times can drop below what is required for a sharp shot. Also, the 2.8 aperture isn't always that useful. In case you need to increase your DOF or want the slightly higher quality that smaller apertures provide, you need to stop down. |