Ultra wide lens for my Full frame camera

Hello everyone!
I'm looking for a ultra wide lens. Almost of time uses for landscape. My concerned about Canon 17-40 or Sigma 12-24 version II
- Canon 17-40: L family series, no idea about built in, quality and weather seal, 77 mm for filter (I have some 77mm filters). But I confused about the range, is it a big difference from 17 to 24 mm? (Because I have 24-70mm).
- Sigma 12-24 version II: I like the range of this lens. It's an attractive with me. But no filter can be use with it.
Any your opinion are appreciate!

A 17mm lens on a full-frame (135 size) offers a field that is about 93 degrees wide. In comparison, the 24mn offers about 74 degrees. This is quite a difference indeed.

I find that exploiting a 17mm requires me to get quite close to the subject, which produces extreme perspectives. It does work as a do-everything lens but it is quite easy to create uninteresting images with ultra-wide angles.

Here are a couple that used a 17mm... First a 17-40L on a borrowed 5D2

IMAGE LINK: http://www.flickr.com …s/noisejammer/5​009920215/

IMAGE LINK: http://www.flickr.com …s/noisejammer/5​101536596/

IMAGE LINK: http://www.flickr.com …s/noisejammer/5​031518185/

the 4th pic here, shows the difference between 17mm and 24mm...you can also see just how crazy wide 12mm is

http://www.juzaphoto.c​om/article.php?l=en&ar​ticle=8

Big difference between 17 and 24

DreDaze wrote in post #15090917
the 4th pic here, shows the difference between 17mm and 24mm...you can also see just how crazy side 12mm is

http://www.juzaphoto.c​om/article.php?l=en&ar​ticle=8

That's a great illustration, all of them, actually. Thanks for posting!

Thanks all!
Now I still have another question: If EF 16-35mm f/2.8L (version I) used and sigma 12-24 (version II) brand new are same price. Which one is the best choice?

Neither is very sharp in the corners, but the sigma goes way wider and is much shorter. It sounds like you want a true super ultra wide and that would be to sigma. The version 2 is supposed to be improved over the original in terms of sharpness. I say that also considering you have the 24-70 so the 16-24 is what you are really buying with the canon. I assume the 24-70 is better anyway from 24-35, but that is just an assumption having only used one of the two but not compared both.

I like my 17-40L. Scrubs up nicely with DPP/DLo if you need the absolute sharpness.
Far corners are a bit grubby though even stopped down.

IMo I would use wider for seascapes and star shots.

I'm thinking about the filter. At 17mm (17-40mm) with filter can do more than at 12mm (12-24mm) wide.

philubonmat wrote in post #15092493
Thanks all!
Now I still have another question: If EF 16-35mm f/2.8L (version I) used and sigma 12-24 (version II) brand new are same price. Which one is the best choice?

I use the 16-35 II really like it on FF. For me is 12mm to wide.

philubonmat wrote in post #15090653
Hello everyone!
I'm looking for a ultra wide lens. Almost of time uses for landscape. My concerned about Canon 17-40 or Sigma 12-24 version II
- Canon 17-40: L family series, no idea about built in, quality and weather seal, 77 mm for filter (I have some 77mm filters). But I confused about the range, is it a big difference from 17 to 24 mm? (Because I have 24-70mm).
- Sigma 12-24 version II: I like the range of this lens. It's an attractive with me. But no filter can be use with it.

Any your opinion are appreciate!

The Sigma does accept a filter, though only in a slot between the camera and the lens. I use .6NDs (using two if needed) and they work great. The only thing is, you cant use a polarizer, unless you create a lee-holder adapter. Great lens, though...
http://www.flickr.com …s/sets/72157628​631722739/

If you want extreme wide, it's about the widest you can go, I believe, on FF. Be wary of distortion that wide, though.

It is a light-hungry lens, too - keep that in mind..

I view a 17-40mm / 16/35mm as a general purpose wide angle zoom lens and the 12-24mm as a specialty ultra wide angle lens. I love my 12-24mm (ver1) for what it does but it's too wide to be used as a walkaround lens. I'm not a fan of UWA for landscape (i prefer normal/tele) so I can't really comment on that use.

Finally, I have decided to get 17-40mm L. Thanks all comments!

Logicus wrote in post #15094544
The Sigma does accept a filter, though only in a slot between the camera and the lens.

I'd noticed that slot on mine, but never seen anything that would fit it - where did you get yours from?

philubonmat wrote in post #15101025
Finally, I have decided to get 17-40mm L. Thanks all comments!

The 17-40L is a really nice lens, later if you want to complete with something wider you can watch at the Samyang/Rokinon 14mm f/2.8 which is a (utra-ultra-wide) gem!

Titi