Pro/Cons for Sigma 12-24 II & Canon 16-35 II

vvv14 wrote:

I'm looking for a wide angle zoom and I narrowed my search to these two lenses. I intend to use them on a full frame (5d3) mostly for landscapes but some architecture as well.

The main criterion of selection is sharpness. A prime would do a better job but, as an amateur I can’t justify the price of a good prime, plus the zoom is handy.

Actually, there is one prime that might fit your bill by being both inexpensive and having impeccable image quality (except one feature that can be post-corrected).

The too-good-to-be-true Samyang 14 mm f/2.8 E AS IF UMC has been my and many others' wide angle choice since they re-engineered the glass (the old version didn't have UMC it its name and it was a much worse lens). The lens costs less than 350€ in Europe, so it is by any definition a dirt-cheap piece of glass. It is also sold by many other brand names, but I don't know if they are the non-UMC or the UMC version.

When Canon's 14/2.8L II costs over seven times that much, you wouldn't think you could get anything usaful for 350€, but the Samyang is one wonderful piece of glass. The lens is mechanically sound and the focus ring has the MF era feel that is smoother and better than on any L lens I've used. 14 mm is wiiide, and usable even with fully open f/2.8 aperture.

Sounds too good to be true? Well, don't believe me. Have a look at what PhotoZone and LensTip say.

My Pros:

• Sharp. Bitingly sharp. And did I say it was sharp?
  
• Mechanically sound.
• Good flare resistance.
• Nice saturated colours. At least part of it comes from the good flare resistance.
  
• Surprisingly good bokeh if you shoot nearby subjects with fully open aperture. Of course bokeh isn't the reason to buy a super wide, but it doesn't hurt either, does it?
  
• A joy to use.
• No chromatic aberration. None. Zero.
  

My Cons (there always has to be some...):

• The lens is fully manual. You focus yourself, you set aperture yourself. However, with a 14 mm lens and its native depth of field, manually focusing really is easy.
• The lens has complex moustache distortion, and a lot of it. Not often problematic with nature, but worse with architecture. This can of course be corrected with software. And, actually, because it is moustache distortion (edges less distorted than areas closer to the center), minimal amounts of focal length is lost when correcting for it. As everything in lens design is a compromise, my guess is that the engineers designing the Samyang decided to let the lens have lots of distortion to get both sharpness and good chromatic aberration. In my opinion that was a great compromise.
  
• The distance scale is way off on many copies. If you cannot select your copy, this is something you just have to live with. So learn that e.g. 3 meters actually means infinity. I'm not too happy about this, but I'd rather take this fault than bad IQ.

So, there you are. I know I didn't directly answer the question you made, but thought you might still be interested.

I'll end this message with two, no, make it three quotes.

PhotoZone: Well, we were stunned by the results in this category and I reckon you will join us once you've had a look at the charts below. The Samyang produced nothing short of outstanding resolution figures for a lens in this class. [...] I reckon that you will not believe us so please have a look at our field image section.

LensTip: Honestly, I’ve never expected I might sing the praises of a low-end lens produced in Korea. As you see, though, an excellent image quality is not just a privilege of expensive devices produced in Japan or Germany.

LensTop: It’s enough to say that it definitely surpasses in image sharpness the expensive, professional Nikkor 14-24 mm f/2.8 set at 14 mm and also it corrects most of optical aberrations better than that lens.

Kind regards,
- Henrik