# Wide Angle Lens: Sigma 10mm-20mm or Canon 17-40mm L



## chelveez (Feb 4, 2011)

Hello!

I'm looking for a good, affordable ultra wide angle lens.

I've been going back and forth between the Sigma 10-20mm f/4-5.6 and the Canon 17-40mm f/4 L.

It seems obvious to get the L...BUT, here's what I've been thinking

Sigma: $425 used, $465 new
Canon: $645 used, $789 new
about a $200 difference

Sigma: *10*-20mm
Canon: *17 *-40mm (would it really give me that ultra wide angle I'm looking for? 7mm more seems like a big difference...)

Sigma: f/4-5.6
Canon: f/4
Is there a big difference here? I would probably stick to the widest angles...so wouldn't the sigma be better since it it goes as wide as 10mm rather than 17mm? The F stop would be 4 for both.

Does the "L" and Canon brand make a $200 dollar difference in addition to it not being as wide as the sigma?

I feel like the Sigma would work better for me, because I really to get those ultra wide shots...that 10mm is really appealing...but then again, the Canon and L thing is keeping me from really making a solid decision.

Any of you have experience with either lens?? How is focusing, speed, and clarity?

Would appreciate any feedback! Thanks.


----------



## Big Mike (Feb 4, 2011)

They are both called 'wide angle' lenses...and they are.  But the 17-40mm was designed for use on 35mm SLR film cameras, where 17mm will give you a ultra wide angle of view.

Most Digital SLR cameras have a sensor that is smaller than 35mm film, so the edges of what the lens sees, are cut off....cropped.  So on most DSLR cameras, you need a shorter focal length to get an ultra wide angle.

What lens do you have for you camera now?  Something like an 18-55mm zoom?  If so, 17mm will only be slightly wider than 18mm.
10mm, on the other hand, will be much, much wider.


----------



## quiddity (Feb 4, 2011)

what about the tokina 11-16


----------



## Big Mike (Feb 4, 2011)

> Does the "L" and Canon brand make a $200 dollar difference in addition to it not being as wide as the sigma?


To some people yes...but maybe not to others.

Actually, the Canon EF 17-40mm F4L is one of the most affordable 'L' lenses and is quite the bargain...giving you great quality at a 'good' price.

My ultra wide angle lens is the Canon EF-S 10-22mm.  It's not an 'L' lens, but maybe only because Canon doesn't give EF-*S* lenses the L designation.  I've heard many say that it's image quality is on par with many L lenses.  It's also quite a bit more expensive than the Sigma 10-20mm, for example.  

I don't think you ever mentioned what camera(s) you have.  If you have a 'full frame' digital body, then you can forget most of these 10mm lenses...because they are made for 'crop' sensor cameras only.


----------



## chelveez (Feb 4, 2011)

That helps so much! Thank you. I have a Rebel XT...I'm looking to upgrade to a 7D or 60D. So Sigma it is!? I am looking for that wider angle.


----------



## Overread (Feb 4, 2011)

I'd also suggest considering the Sigma 8-16mm which is wider than the 10-20mm (remembering that the 4mm difference will be noticable at this short focal length) and also is a class higher (from all the reviews I've read) than the 10-20mm


----------

