Canon EF-S zoom lens - 17 mm - 55 mm F/2.8

Having owned and used a Canon EF-S 17-55mm f/2.8 IS USM zoom lens for around 15 months, I feel that I have some well balanced experience with it.

Being an EF-S lens (the 'S' standing for 'Short' back-focus), it is designed for use ONLY with cameras having APS-C size sensors. Do not attempt to use one on a full-frame DSLR or 35mm SLR camera. Firstly, such lenses have a reduced image circle which will produce severe vignetting on large ...
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On a Canon APS-C size DSLR, this 3.2x zoom provides a useful range of focal lengths from 27.2mm to 88mm with a maximum aperture of f/2.8 which is consistent throughout the zoom range. This fast aperture makes the lens eminently suitable for low-light work, particularly as it also boasts a 3-f/stop IS (Image Stabiliser), making it possible to attain pin sharp images at surprisingly slow shutter speeds, providing of course, the subject ... more

Having owned and used a Canon EF-S 17-55mm f/2.8 IS USM zoom lens for around 15 months, I feel that I have some well balanced experience with it.

Being an EF-S lens (the 'S' standing for 'Short' back-focus), it is designed for use ONLY with cameras having APS-C size sensors. Do not attempt to use one on a full-frame DSLR or 35mm SLR camera. Firstly, such lenses have a reduced image circle which will produce severe vignetting on large sensor cameras and secondly, the mount of the rear lens element could be struck by the camera's mirror, causing serious damage.

On a Canon APS-C size DSLR, this 3.2x zoom provides a useful range of focal lengths from 27.2mm to 88mm with a maximum aperture of f/2.8 which is consistent throughout the zoom range. This fast aperture makes the lens eminently suitable for low-light work, particularly as it also boasts a 3-f/stop IS (Image Stabiliser), making it possible to attain pin sharp images at surprisingly slow shutter speeds, providing of course, the subject isn't moving. IS cannot prevent subject movement, ONLY camera movement. At this, it is extremely effective.
The IS is quite clever in that it can also detect when left 'on' if the lens is static so there is no need to turn the IS off when tripod mounted.

This is a very well constructed lens and although most of the structure and body is of plastic (polycarbonate), it is high quality and the lens feels very well made indeed. There is none of the sloppy zoom creep which is evident with the less expensive 17-85mm f/4-f/5.6 IS USM and the lens is significantly larger and more 'substantial' than the cheaper lens. Part of this impression is no doubt due to the relatively large pieces of high quality glass used in the construction. However, on the smaller 'entry level' DSLR's, the lens can seem a little 'unbalanced', making smaller cameras feel somewhat front heavy. This isn't too much of a problem once you've got used to using the lens itself as the main support when the camera is in the hand.

Unfortunately, like many Canon EF-S lenses, it doesn't come supplied with a lens hood and while the lens isn't particularly prone to flare, due to the large front element and wide angle, the EW-83J hood is really an essential. It's not cheap but, get one anyway!

The lens extends quite considerably during zooming, making it slightly more unwieldy on small cameras. However, I use my one on a EOS 400D and have no problems with it at all. The front element does not revolve during focusing or zooming so, using polarisers is no problem.

AF is extremely fast and being of the ring type USM, is also quiet and very accurate. FTM (Full Time Manual) focusing is available even when set to One Shot AF. However, this lens focuses very accurately, even in low light, due to some extent to the fast f/2.8 aperture . Manual focus adjustments are therefore rarely needed. The lens focuses quite close too - down to 0.35m which although not 'macro', does provide great close-up potential.

The lens tends to vignette quite a bit at full aperture at all focal lengths but this becomes less of a problem on stopping down just one stop to f/4. Distortion is not too much of a problem however. Sure, there 'is' barrel distortion at 17mm but this is almost neutralised by the time you have zoomed in to 24mm. Slight pincushion distortion becomes evident at 55mm setting but this shouldn't really be noticeable unless photographing architecture with straight lines near the frame edges.

Resolution or 'sharpness', is extremely impressive. At 17mm to 24mm, it is extremely good, even at full aperture, in the centre of the frame. The edges/corners are a little behind, but even here, performance is very good. Stopping down to f/4 or f/5.6 improves sharpness still further when edges and corners jump into line also. It holds this fine performance right through the aperture range until diffraction spoils quality (as can be expected) at very small apertures.

Ultimate image quality isn't perhaps quite as high at the 55mm end of the zoom but even here, it is really quite impressive, especially at f/5.6 to f/8. Unusually for such a lens, CA's (Chromatic Aberrations) are not a significant problem and unless shooting thin dark objects against a bright sky, will for the most part, go completely unnoticed.

A truly great lens. If they (Canon) had made it out of Magnesium Alloy, it would be a top-of-the-line 'L Series' lens no doubt. The fact that it isn't makes it perhaps something of a bargain although, it has to be said, the lens certainly isn't 'cheap'. By the time you factor in the quite expensive EW-83J hood, you're looking at a fairly substantial amount of money. However, in my opinion, money well spent!

David Chamberlain 

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