[DeWalt Dave]

Hi,
I've got a Canon 400d with an 18-55 and a 55-200mm lens.

I want to get a wide angle lens - say something around 24mm for a wide angle capability. But isnt 24mm already covered by my 18-55 lens ?

[Chris83]

Your correct in thinking your 18-55 already covers 24mm. If your wanting something wider than what your kit lens can achieve then you need to be looking for something below 18mm, like the Canon 10-20mm etc

[The Android]

You seem to have answered your question yourself - Yes your 18-55 covers 24mm.

However 24mm isn't really considered to be wide angle (especially with the 1.6 crop factor of your sensor).
You should probably take a look at something like the Canon 10-22mm EF-S for wide angle.

[DeWalt Dave]

Ok guys, thanks - gulps at £480 price tag.

[The Android]

There are cheaper options if you opt for Sigma or Tamron.

[Fozzybear]

If you're looking for the wide view of a 24mm lens on a film camera (which is a great wide-angle, I used to use a 24mm on my old film SLR) then you're looking at a 24mm/1.6, which is about 15mm. The reason is the smaller sensor of the 400D - an 18mm len on the 400D 'looks like' a 28mm lens on a film camera.

As Android says, you can buy other lenses that are cheaper. I paid £300 for my Sigma 10-20mm (equiv. to a 16mm to 32mm lens on your Canon) and there are Tokina and Tamron ultra-wide zooms too.