So I bought a Canon EF 17-40 L lens to replace the EF-S 18-55 I got when I was a tight arse. No point in spending money for the high quality stuff when you’re starting out and won’t know the difference, I figured. Quite a few people rave about this lens, being one of the cheaper ‘L’ lenses Canon offers. If you didn’t know, ‘L’ is the designator Canon gives their highest quality lenses. ‘Quality’ as in sealing, manufacture, image, focus speed, low-light characteristics, chromatic abberration. In directly tangible terms, L lenses are big, heavy, and have a red line around the outer edge. Like many hobbies involving expensive toys, photography enjoys its fair share of wankery, and there is a large segment of the community that has a “equipment-first” mantra. I can honestly say that having this super-dooper lens and camera has not led to me taking better pictures than with the much cheaper high-end Nikon Coolpix. Anyone who thinks that equipment is the way to better photographs is fooling themselves. Michal Daniel’s work makes this point.
So with all that out of the way, here is a very rough visual comparison of the two lenses I have (note that lens quality varies from copy to copy). I tried to match the focal length, and framing. The images shown here are crops from unprocessed originals, at 200%. On-camera sharpening and contrast enhancement is disabled. Images between the two lenses were taken within 2 minutes of each other.
Since I’m most interested in wide angle, here is a crop from the center of the image (which should be the sharpest) taken with both lenses at f/4 and f/8:
There are differences, but they are pretty marginal. Differences really show up on edges however (this taken from the upper-left corner):
Now lenses have ‘sweet spots’, and typically any zoom lens will perform worse at the extremities of their range. By ‘stopping down’, i.e., using a lower f-number, you can help alleviate the problem. See the difference between f/4 and f/8 in the above image for example. It’s my impression that the 17-40 has a longer usable range than the el-cheapo – as it should for the price.
So to sum up, the images I’m getting from the 17-40L aren’t as amazingly spectacular as I was led to believe. People talk about great contrast and crisp colours. I don’t see it, there’s just not an eye-popping difference. So if you’re thinking about the 17-40L, and you’ve already got the kit lens, give it some thought. If you want to go über bild qualität, try a EF 16-35 L or a prime. I think a EF-S 10-22 would of suited me better.
