Canon EF-S 10-22mm f/3.5-4.5 USM Lens

This lens was created to fill the hole in Canon's range for a super wide angle lens for their range of EF-S mount DSLR's.

Fortunately, since it inhabits a unique position in the range, it is a superb lens and there is no real alternative (from Canon anyway) that covers the same focal lengths.

It's not an L lens so don't expect weather sealing and and lens pouches/lens hoods in the box. Do expect a very well built lens with excellent image quality.

The lens has a very close minimum focusing distance of 24 cm which can be useful for odd effects at the wide end of things. The zoom and focusing rings are smooth and well placed. The lens takes huge filters (77mm) which can add a lot to the purchase price but should be considered essential as the front element is very convex and should be protected. A useful tip - get the slimmest filters you can for this lens as the lens is so wide angle standard filters will cut off the corners a fraction in the frame.

Image quality is excellent. DOF is almost a non issue with this lens as even at minimum aperture and focusing distances greater than close range everything seems to be in focus. There is no appreciable increase in sharpness when stopping down either like you get with some lenses. I leave mine at around f5.6 all the time because I read somewhere that this is the sweet spot for the lens (it's all sweet but apparently this is marginally sweeter). There is a little bit of colour fringing that can creep in for backlit subjects but nothing that can't be edited out and it's par for the course for a lens of this type. What is probably better than normal in terms of performance is the lens' control of flare which is very good. I haven't had flare in my shots even with the sun in the frame. There is no noticeable pincusion/barrel effect either. Solid performance all round.

So if you have an EF-S mount Canon there really are not many choices out there for a super wide lens. It's not the cheapest but it probably is the best out there right now.

Explaining the name of this lens:
Canon - manufactured by the same people that made your camera. They'll work together perfectly.
- EF-S - only works on APS-C "crop-sensor" cameras - for example the 600D, 550D, 60D, 50D and 7D, as well as some older models like my own 20D
- 10-22mm - on your APS-C camera this gives a field of view equivalent to 16mm on a full-frame or film camera at the wide end (ultra wide angle) down to 35mm when zoomed-in (a regular wide angle lens).
- f/3.5-4.5 - maximum aperture is not that great. Particularly being a wide angle lens, it won't be easy to achieve narrow depth of field if you want it. It's also not going to very good for shooting indoors in ambient light, or even outdoors for freezing action in dim conditions. (If you really need a faster ultra wide angle lens, consider the Tokina ATX 116 PRO DX AF11-16mm F/2.8 Canon)
- USM - the autofocus motor works quickly and quietly - especially if compared to the kit lens that came with your camera.

This lens is manufactured using the same high quality glass Canon uses for it's professional "L" lenses. (However it does not carry the "L" identifier as Canon do not apply this to EF-S lenses.). As it doesn't carry the "L" identifier, Canon don't bundle the lens hood - and with a lens this wide you really need one to prevent peripheral light sources from degrading the contrast and colour definition of your image. Canon's offering is expensive (Canon EW-83E Lens Hood For EF-S 10-22mm f/3.5-4.5 USM, EF 16-35mm f/2.8 L U, EF 17-40mm f/4.0 L USM) but you may find cheaper 3rd party alternatives.

The optical quality of this lens is very good, and certainly adequate for most professional purposes. On real-world subjects (rather than test charts), in-focus sections of the image are extremely sharp from the centre out to the corners. Colour rendition is very accurate, and contrast is good. Chromatic aberration and lens distortion are there if you look hard enough, but don't really impact on real images. While depth of field tends to be great, when you do have bokeh it has a very pleasing smooth quality. With it's small maximum aperture, it's not easy with this lens to blur out the background.

If you're not used to using an ultra wide angle lens, you will need a certain amount of thought and practice to get the best results out of this at its widest - composition is perhaps even more important than with longer focal lengths, and small changes in the position and angle of the camera can have a huge effect on the impact and effectiveness of the final image. You generally need to get very close in to the foreground elements of your composition. At 10mm, the lens is very good for internal and external architectural shots and for creative/artistic compositions. Zoomed-in to 22mm this becomes a more standard wide angle lens and produces more sane results - making the lens good for landscapes and group shots.

At wider angles and especially with the hood fitted, using the pop-up flash on your camera will leave a shadow area at the bottom of your frame. Fix this either by removing the hood and zooming in a little or - much better - using an off-camera light source.

I absolutely adore this lens. Given the very wide angle you can pull off some very creative shots with this it. It is a fantastic portrait lens, allowing you to get close to the subject whilst still having a lot of the background visible.

The close minimum focus distance of only 24cm is a great and very useful feature!

It also works really well when used for Astophotography! I have taken some absolutely stunning pictures with this lens aimed at the nighy sky!

Very low distortion from this lens even at its widest, its not an L series lens but it may as well be - the glass is of incredible quality although unlike most L lenses are it is not weather sealed as mentioned in another review.

Overall this lens comes at a cost but the pictures you can take with it make it a worthwile addition to your kitbag!