Although this lens is considered as ultra wide lens, for XTis and 30D's, this is really a 28-65mm lens (not "ultra" but regular wide). I purchased this for about $700 at Amazon to replace the kit lens 18-55mm the XTi came with. I am very pleased with the photos that I am taking. The focus is quick. The images are sharp, and the color is beautiful. I like the lens a lot. Because it's a F4 lens, I do need to use the flash. With 430EX flash I am getting pleasing shots in low light situations as well. I suppose a lower F stop might be better but I don't think Canon makes a lower F stop lens of comparable build. I did consider 28-70mm F2.8L (45-112mm on the XTi), but then it's no longer a "wide" angle lens. Compensating for the crop factor, getting a wide angle lens meant 17mm or less. So, this was really the only choice I had for an L quality build at this price range. Over all, I am very satisfied with the build quality and the results. The 40mm (64mm on the XTi) is a bit short, and I wish it were longer. However, giiven that this lens costs only (did I say "only?" lol) about $650, I have no complaints about the lens. Something's gotta give. It's weight is nicely substantial (not too heavy), and since I use my XTi with a battery grip all of the time, the combined weight balances well in my hands. To me, the battery grip and this lens are perfect companions to make the XTi's complete. I like this 17-40mm f/4L USM Wide Angle Zoom Lens for my XTi.

Super fast F1.4, this lens covers all the bases, from quality glass to weather resistant sealing. This lens is perfect for landscape photography and for traveling light. I'm solely a prime lens user, and this one is always in my bag.

Great lens for portraits!Even though it is made of plastic, it has a really sturdy build. The bokeh produced is beautiful at f/1.8.

Needed some quality protection for my Nikon AF-S 80-200 f2.8 lens. Works great and the price is superb.

Every pro reviewer is quick to point out this will prevent autofocus with slow lenses--but today I discovered that with this extender attached, both a Canon 5D4 and a Canon 7D2 will autofocus a Canon 100-400 L f/5.6 lens just fine in Live View. On a 5D4 it registers as a minimum f-stop of f/11; on the 7D2, it shoots at f/9. No idea why that is. However, both cameras were able to autofocus the lens in Live View without any particular problem. Yes, the autofocus is slow compared to normal use but that's inherent in the design (and way beyond either my understanding or the scope of this review). My quickie test was random shots in my backyard in full sunlight; I also put a 10-stop ND filter on and shot the full sun. Autofocusing the sun is a little tricky but setting the focus square on the diameter gives it an edge and then it locks right in.The only other test I did was with a Canon 135L f/2 lens; the 5D4 autofocuses through the viewfinder, giving a 270mm f/4 lens. Not sure what good that is but now you know. Didn't try it with the 7D2.

I'm liking this lens on my r7. I have much nicer 400L but this lens is light and travels well. F8 is not so amazing but it gets sharp bird photos in daylight.

Fits perfect on my Leica 28mm f2.8 Elmarit lens.Fast delivery, arrived early.Thank you Amazon.

Best lens for the money. I should not have waited so long to buy it. Original photo shot in raw, ISO 100 f1.8 at 1/800 AWB. Canon 60D body with this awesome 50mm lens.