wide angle lens

[spako]

Hi,

I'm currently owning a Canon 350D with a wide angle lens (Canon 17-40mm) and I was wondering if a 10-20mm would be a good addition to this or if it would just not be worth the money as I already have the other lens... are those 7mm really significant or should I consider buying some other gear?

I would really appreciate any advice on this!

 

[fmw]

Differences in angle of view when compared to focal length travel in a geometric fashion. What that means is that angle of view changes get smaller and smaller as focal length increases and larger as it decreases. 7mm at the telephoto end of things is fairly meaningless. At the super wide angle end of things it is huge. It isn't the change in focal length that matters so much as the change in angle of view. You can look up the angle of view figures for any lens yourself and see what I mean.

 

[Sw1tchFX]

That's a huge difference. If you can use it, go ahead. I don't usually find situations where I need to go wider than 17mm on my body, so a 12-24 probably wouldn't be used much.

 

[JIP]

I think if you will use it why not.