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

vvv14 wrote:

Robert, thanks for your reply.

I own both the Canon 17-40 and the Sigma 12-24 Mk II.

Am I correct to assume you acquired the Canon prior to Sigma? You plan on keeping both?

When I need a wider lens than the Canon (quite often when photographing covered bridges) I use the Sigma.

Does this mean that you prefer Canon at 17mm and over?

Now, perspective distortion is an other story on loss of image space but that is what you have to work with all UWA lenses, including primes.

Can you roughly quantify the loss on image space in any way or is it more like a "case by case" scenario (i.e. shoot at 12mm and after distortion correction looks like it was shoot 14mm)?

I too own both the Canon 17-40 and Sigma 12-24.  I had the Canon for about 2 years and decided to get the Sigma 12-24 II last summer because I enjoy architectural photos and wanted something wider. I find that the Sigma 12-24 is significantly wider and a joy to use.

In reference to your last question with respect to 'space', I am assuming that you are asking about how much of the photo is lost when distortion is corrected. This really depends on the angle your camera is relative to the surface of the earth. If you are pointing your camera completely parallel to the earth, then distortion is next to nothing. However, the more angled your shot, the more distortion is created. Of course, the more distortion means that the more space will be lost in your photo.

I have provided two photos taken about 1-1/2 years ago when I was testing the 12-24 Type I lens. It was a rental but built like a brick. The quality of Type II is equally good although they have removed the "EX" designation which means that there is less warranty coverage. I think that it went from 10 years of warranty coverage with the Type I which has the "EX" designation to 5 years with the Type II lens without the "EX" designation. I find this very strange but warranty coverage will vary from region to region. Make sure that you check for your region.

You can see from the two examples below that the distortion correction caused a small amount of 'lost' space. This is primarily because my shot was slightly angled.



Sigma 12-24 Type I - With Distortion

Sigma 12-24 Type I - Distortion Corrected