Never bought any of the Canon L series lenses, wondering if the cost is worth it over my current lens. Do you think I will notice improvement in my wide angle images?
Thanks for any thoughts.
Kevin
Posted by Kent Mearig on January 22, 2010 at 8:20 AM
I don't have any frame of reference in the form of experience with the sigma, but I can say that by far the biggest weakness of the canon is in the edges and corners that won't be revealed by the 50d. I've been pleased with the performance of the 17-40L over the last half year or so, but its optical quality does reflect that it's one of the cheapest L lenses out there.
Posted by Kevin Trinkner on January 22, 2010 at 10:31 AM
Thanks for the link Matt, great info in that post!
Posted by Wayne Jones on January 22, 2010 at 1:32 PM
Kevin,
Darwin and others can answer the question about the two Canon L lenses. But as for your original question about the Canon 17-40 vs. the Sigma 17-70 on APS-C sensors: Beside the extra reach of the Sigma, the main difference between the the two is the better build and weather sealing on the Canon. The image quality on APS-C sensors is nearly identical, according to the test results on www.slrgear.com/ and http://www.photozone.de/ Of course, the Sigma will be useless on a full-frame body, but it's more versatile and at least as sharp as the Canon on your 50D.
Thanks Wayne, that really was the main question I have. Sounds like it's probably not worth the upgrade until I move into a full frame camera...
Kevin
Posted by Gene Lugo on January 22, 2010 at 3:36 PM
It seems that both lenses are more or less equivalent in the 17-40 range, but I would caution you to consider quality control with the Sigma. That being said, I use the 18-50 2.8 which can provide exceptional performance, but it took me 3 tries, each time returning it to Sigma's Ronkonkoma, NY facility, to get a good one. At the end of the process I got a lens that exceeded even the service rep's expectations! I would go that route rather than deal with the seller, because a replacement lens will be evaluated on an optical bench, so you have a better chance of getting a good copy.
Things to look out for that signal an assembly issue requiring a replacement - uneven sharpness across the image, uneven light falloff, "smearing" or "tearing" of the image along an edge or in a corner, and softer results overall at the 50mm setting. Things like pincushion or barrel distortion, softness in the corners at the wide end especially when wide open, and some chromatic aberration is expected and should not be a reason to return it. The unevenness is a sure thing though.
I also own their 10-20, 150 2.8 macro and a 50-500 along with various pieces of Nikon glass, and I cannot say enough good things about the Sigma products on the whole.
Discussion
7 repliesWorth the upgrade cost for my Canon 50d?
Never bought any of the Canon L series lenses, wondering if the cost is worth it over my current lens. Do you think I will notice improvement in my wide angle images?
Thanks for any thoughts.
Kevin
Eventually I do plan on getting a full frame Canon. Do you feel the 16-35L is sharper on the edges?
http://www.naturephotographers.net/articles0508/dw0508-1.html
Matt
Darwin and others can answer the question about the two Canon L lenses. But as for your original question about the Canon 17-40 vs. the Sigma 17-70 on APS-C sensors: Beside the extra reach of the Sigma, the main difference between the the two is the better build and weather sealing on the Canon. The image quality on APS-C sensors is nearly identical, according to the test results on www.slrgear.com/ and http://www.photozone.de/ Of course, the Sigma will be useless on a full-frame body, but it's more versatile and at least as sharp as the Canon on your 50D.
Thanks Wayne, that really was the main question I have. Sounds like it's probably not worth the upgrade until I move into a full frame camera...
Kevin
Things to look out for that signal an assembly issue requiring a replacement - uneven sharpness across the image, uneven light falloff, "smearing" or "tearing" of the image along an edge or in a corner, and softer results overall at the 50mm setting. Things like pincushion or barrel distortion, softness in the corners at the wide end especially when wide open, and some chromatic aberration is expected and should not be a reason to return it. The unevenness is a sure thing though.
I also own their 10-20, 150 2.8 macro and a 50-500 along with various pieces of Nikon glass, and I cannot say enough good things about the Sigma products on the whole.