Canon 17-40mm f4 L USM
This was the first lens I bought to go with my Canon 20D and was followed by a Canon 70-200mm f2.8 L USM shortly after. Since the 70-200mm left me dazed and in awe over it's ablility to take tac sharp photos it took me some time to fully appreciate what the 17-40mm can do. So what is the 17-40mm good for?
The most obivous use of any wide angle lens is perhaps landscapes or architecture. Since both these types of photography, when done seriously, involve using a tripod the relatively slow f4 aperture of the 17-40mm is a non-issue. This is also the case for night photography where the 17-40mm is my primary working lens.
The 17-40mm has a small minimal focal distance of 0.28 m (0.92 ft) and a magnifaction factor of 0.24 at 40mm. This means you can get up close and personal with your subject. For example on the left (photo by lovebottom) you can see my lens close to the minimal focal distance from a snake and on the right the resulting photo.
Getting up close at 17 mm can also provide some interesting distortion and effects. Roughly speaking the objects closest to the lens will appear over sized and the objects on edges will exhibit some curvature.
Indoor lighting is generally poor for photographic purposes. With the 17-40mm wide open at f4 you will be required to use ISO 1600 or 3200 to maintain a shutter speed high enough to prevent motion blur due to camera shake. This is not an available light lens, f4 is too slow.
Stuff to note:
- Although the 17-40's overall length does not change while zooming, the end element does move back and forth inside the lens barrel. I would suggest getting a hoya super 77mm UV filter or some other multi-coated 77mm UV filter to completely seal the 17-40mm from dust and water.
- The hood is big, wait, I mean massively wide compared to the lens barrel. The reason for this is to prevent the hood from causing vignetting at 17mm on a full frame camera. As a side effect the pop up flash on a 300D, 350D, 400D, 20D, or 30D is blocked by the hood.
The Canon 17-40mm f4 L USM has a slow aperture at f4 and is no where near a sharp as a Canon 50mm f1.4 USM or the Canon 50mm f1.8 for that matter but you should not expect it to be. It is also true that the 17-40mm as a macro lens is no match for the Canon 100mm f2.8 USM macro's 1x magnification but then the 100mm can not get that cool wide angle effect. Where am I going with this...no one lens has it all but what you get in the 17-40mm is pretty darn good.
Check out more 17-40mm shots here and the 17-40 flickr group here.