Superwides: Canon 10-22 vs Tokina 12-24
For landscape photography, a really wide lens can often give a dramatic perspective – especially if there is something close to camera in the foreground to give the image depth. Even for nature photography, where telephoto lenses are prized for their ability to draw a subject closer, a wide angle lens can be useful for setting animals or plants within their environment. And, for some photographers, the wider the better.
But, there is an issue when it comes to getting really wide perspectives using entry-level digital cameras and prosumer models such as the Canon 40D and Nikon D300: the crop factor – whereby only a portion of the imaging circle of the lens is used – means that the image is effectively magnified compared to that produced on a camera with a full-frame sensor using the same lens, thereby negating its putative perspective. A 28 mm lens may be regarded as a standard wide angle on a 35mm film camera or digital camera with a full-frame sensor (such as the Canon 5D, Nikon D3 or the newly announced Nikon D700), but on a Nikon D60 or D300 that would effectively become a 42 mm lens, while on the Canon 450 or 40D, it would be transformed into a 45 mm lens.
Fortunately, for those wishing to use super wide angle lenses on crop cameras, the manufacturers have come up with a solution: extremely wide angle lenses. The Canon 10-22 f3.5-5.6 is one such lens. Intended to be mounted on Canon cameras with a 1.6 crop factor (ie those that can take EFS designated lenses), it produces images with an effective focal length of 16-35 (the same as that of the flagship 16-35 mm f2.8 L lens optimized for use with the 1D series of cameras). Perhaps its main rival when it comes to image quality is the robustly-made Tokina 12-24 f4.
Like many photographers before me, I was faced with the decision of which of the two lenses to buy? Note that I had ruled out similar offerings from Sigma (due to distortion issues) and Tamron (due to the more limited focal range of the zoom then on offer). Let me also state from the outset that producing lenses with such wide fields of view naturally involves compromise. All suffer to some extent from distortion, vignetting and chromatic aberrations.
The Tokina is without doubt the better-made lens. It feels solid with a nice heft when in the hand. Images from it are very sharp but, at the widest setting (where it is likely to be used the most) image quality is let down by pronounced barrel distortion and very noticeable purple fringing. The Canon 10-22 has the advantage of being more than 2 mm wider (measurements show the Tokina to be really a 12.6 mm lens at its widest), which makes a substantial difference to the field of view at the wide end. The Canon exhibits less distortion at the wide end and less purple fringing produced by chromatic aberration. It is considerably lighter and seems to be a more fragile lens.
The first copy of the Canon 10-22 that I tried was noticeably softer than the Tokina. However, the Canon distributor let me take away five copies of the 10-22 and test them against each other, with the result that I eventually ended up with a Canon 10-22 that was at least as sharp as the Tokina, if not a smidgeon sharper (there was a disappointingly high degree of variation amongst the five copies I tested). This was a significant lesson for me in that until then I had taken rather lightly all the claims on the forum boards about soft copies of various lenses: when one pays a big chunk of cash to a reputable company such as Canon, I had thought it only reasonable to expect quality control would ensure that all copies of premium lenses would be within tight tolerances. This is clearly not the case – as my subsequent testing of other lenses has confirmed.
In the end, I went with the Canon because it performed best at the wide end (the main purpose for buying it), whereas the Tokina produced its best images at 24 mm. But, truthfully, there is not a lot in it. Both will open up the doors to a superwide perspective on our world.
One note of caution I would sound: using superwide angle lenses can be an addictive process. They definitely put fun into photography and who am I to bemoan something that makes you a little high? But I am not sure that it does our photography all that much good to give in to the temptation too often; to eschew other focal lengths just because the view down the camera is so different with the superwides. It takes a special set of circumstances to make such wide angle perspectives sing – otherwise the effect is to flatten out horizons and fill foregrounds with space.
My advice, then, is to use them in photography the way you might use chilli powder in your cooking: use only when needed for effect, and then only sparingly.
Canon 10-22 at 10 mm (ISO 200, f4, 1/1600)
Canon 10-22 at 22 mm (ISO 200, f13, 1/125)