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(From Canon lens literature) With the large maximum aperture, excellent background blur is possible even with a fast shutter speed. The aspherical lens element makes the lens compact and corrects spherical aberrations. The image is sharp even at the edges. Lead-free glass is used. Test Notes We tested this lens shortly after we shot the Canon 28mm f/2.8, and found a lot of similarity between the two. As you'd expect, the f/1.8 isn't as sharp wide open as the f/2.8 lens is, f/1.8 being so much larger an aperture than f/2.8 is. At f/1.8, this lens shows a lot of softness in the corners, even on a sub-frame camera. More than that though, we found that the corner sharpness varied radically with very minor shifts in focus. The corners were always soft, but as we progressed through our focus bracket, we found that the blur graph almost "rolled" across the screen, with first one side off the frame being high, decreasing, and then the other shooting up as the focal distance was progressively changed. This made the point of optimum focus very tweaky. The point that gave the best overall results left one side of the plot higher than the other. As usual though, stopping down even slightly made a big difference: Even at f/2, things were much improved, and at f/2.8, the lens was very sharp all over. - In fact, this lens is a shade sharper overall at f/2.8 than does the 28mm f/2.8 lens we tested earlier. From f/2.8 to f/8, the lens is impressively sharp, with diffraction limiting just starting to become a factor at f/11. Surprisingly, light falloff ("vignetting") is very well controlled, reaching a maximum of only about 1/3 EV with the lens wide open, and decreasing to around 0.15 EV from f/2.8 on. Geometric distortion is also pretty low for a wide angle as well, at only about 0.4% barrel. Like the 28mm f/2.8 though, this lens' weak point is chromatic aberration, and again is higher on a subframe body like the 20D with its smaller pixels than it is on a full-frame camera with larger pixels, like the EOS-5D. The chromatic aberration curve of this lens is similar to that of the 28-f/2.8, but is slightly higher throughout the aperture range. All in all, a fine lens at an affordable price. As with its smaller-aperture brother though, we'd like it better with less chromatic aberration. It does get way soft in the corners at f/1.8, but if you're shooting in limited lighting, that nearly stop-and-a-half advantage over the f/2.8 model could be well worth the extra $200-plus. Full-Frame Test Notes: On the full-frame EOS-5D, this lens gets really soft in the corners wide open, and doesn't completely settle down until f/4. Shooting wide open, we again saw the tweakiness with respect to focal distance that we observed on the 20D, and vignetting increased significantly at maximum aperture. (No surprise in that.) It's worth noting though, that this lens does show much lower vignetting on the 5D at f/2.8 than the lower-cost 28mm f/2.8, so if vignetting bothers you, it might be worth paying the extra freight for this lens, even if you don't absolutely need its maximum aperture. As noted in the sub-frame commentary, chromatic aberration was actually better on the 5D than the 20D, a fact that we attribute to the 5D's larger pixels. We were also pleased to see that, while geometric distortion did increase, it was only by a relatively small amount, to just under 5% barrel. If you need a really fast wide-angle lens on your full-frame Canon SLR, this lens could serve nicely, and at an affordable price point too. - But you'll have to be willing to accept a lot of softness in the corners when shooting wide open. CanonEF 28mm f/1.8 USMCanon EF 28mm f/1.8 USM User Reviews8.9/10average of 13 review(s) Build Quality9.1/10 Image Quality8.8/10
10 out of 10 pointsand recommended by photogjack (9 reviews) Relatively small and lightweight, very sharp none This is a great lens on a full frame body, like the 5D or 1Ds series cameras. My copy is significantly sharper and less prone to flare than my 16-35 f2.8 zoom, even wide open and it focusses very quickly (much faster than my 50 f1.4). It is a terrific lens with no negatives. |