Available for AU$449, the Canon EF-S 55-250mm f4-5.6 IS is a lightweight, affordable first or second lens to complement your entry-level or midrange digital SLR. With its 400mm-equivalent focal length, you get the reach and angle of view desirable for shooting portraits and sports, or just to bring the scenes in closer, with the image stabilisation essential to keep those long telephoto shots from blurring from camera shake.
Measuring 108mm long with a 70mm diameter, the 55-250mm accepts 58mm screw-on filters. The all-plastic construction of the lens barrel and mount make this lens lightweight for its zoom range — just 390 grams — however more expensive (and optically superior) lenses have a metal lens mounts and even a metal lens barrel for much improved durability.
Maximum aperture ranges from f4 at 55mm to f5.6 at 250mm, with minimum aperture stretching from f22 at 55mm to f32 at 250mm. Closest focussing distance is 1.1 metres; this remains constant throughout the zoom range.
The 55-250mm has a broad zoom range which, after taking into account the 1.6x crop factor, is equivalent to 84mm to 400mm on a 35mm camera. This, the longest lens in the EF-S range, is compatible with all Canon digital camera bodies using an APS-C sized chip, such as the EOS 1000D, EOS 450D and EOS 40D, but won't fit on cameras with larger sensors, like the EOS 1D Mark III, EOS 1Ds Mark III or EOS 5D.
Optical image stabilisation allows for sharper handheld photos at slow shutter speeds, especially in low light. The IS system compensates in real time for shake and vibration with no degradation to the image. There are two stabilisation modes; the latter has automatic panning detection which automatically turns off stabilisation in either the horizontal or vertical plane when you're tracking moving subjects.
There are large, easy-to-read zoom markings at 55mm, 70mm, 100mm, 135mm, 200mm, and 250mm. While it ships with the de rigeur front and rear lens caps, the lens hood, codenamed ET-60, is optional. We think lens hoods are a sound investment but they really should be standard.
Performance and image quality
In our testing, we found the lens displayed minimal distortion across its entire range, which is excellent for its price class. There's only barely noticeable barrel distortion (where objects appear to curve toward the outside of the image) at 55mm and slight pincushion (where objects appear to curve toward the centre of the image) at 135mm and 250mm. The lens exhibits excellent sharpness at 55mm in our lab tests, and slightly less sharpness at 135mm but still very good. However, fully zoomed out to 250mm the sharpness dropped off to just acceptable. While zooming, the lens maintains its maximum aperture of f4 from 55mm to 85mm, at 100mm it narrows to f5, and turns to f5.6 at about 140mm.
Mounted on our EOS 450D, the lens felt very light given its range, so it was no problem to carry for a day of shooting. The zoom ring is nice and wide, with a quick, fairly well-damped action. There's no lens creep, the unintentional movement of the zoom caused by gravity. The manual focus ring is located at the front of the lens and is very usable and yields a decent amount of control, but it's fairly noisy. We wouldn't buy this lens solely for manual focus; it will work fine when the need arises but doesn't seem to be intended for frequent use. The lens lacks a focus distance scale, although that's common for entry-level lenses. Its front-focusing design, where the front element rotates during focus, should only be an issue with circular polarising filters. Although some might be tempted, this lens' slow maximum aperture range of f4-5.6 makes it a poor choice for use with a teleconverter.
For the entry-level Canon shooter, the Canon EF-S 55-250mm f4-5.6 IS provides an affordable way to gain image stabilisation on a telephoto lens and represents a good option for an entry-level shooter or more advanced users on a budget. When coupled with Canon's EF-S 18-55mm f3.5-5.6 IS lens, you have an effective range of 29mm to 400mm with image stabilisation in two lightweight and compact lenses for not too much outlay. Canon's alternatives tend to be pricey: the Canon EF 70-300mm f/4-5.6 IS USM lens offers a slightly different coverage range, but it's significantly heavier and will cost you over AU$1,000, while the far more compact Canon EF 70-300mm f/4.5-5.6 DO IS USM lens costs well above the AU$1,500 mark.