wideangle lens

[chris-p]

As Geoff has said, it's basically a bent piece of glass that screws onto the front which is sort of equivalent to looking through a milk bottle. It just bends the view outwards.

You can find them all over the web. eBay is the most common place for this sort of thing. Should be able to find loads for less than a tenner.

[AndyStevens]

From reading what 16-35 users have written in other forums/mags, I would test a couple before buying one - they seem to be a bit variable in sharpness and many opt for the 17-40 instead.

There also seems to be a buzz about these http://www.robertwhite.co.uk/products.asp?PT_ID=698