Sigma 14mm f/2.8 EX
Make it Really Wide
My standard wide-angle lens when I work in 35mm is the Canon 17~35mm f/2.8L. This is a very versatile lens and provides coverage as wide as I ever need. For wider coverage I will use one of my panoramic format cameras.
But the digital Canon EOS-D30 changes the equation. With an imaging chip smaller than a 35mm frame, focal lengths are multiplied by a factor of 1.6X. For telephoto work this is a boon, making a 300mm lens, for example, into almost a 500mm. But when it comes to wide angle this means that even ones widest lens probably won't be wide enough in many situations. The 17mm end of the widest Canon zoom only gives 28mm coverage when used on the D30.
The widest rectilinear lens focal length available for Canon EOS bodies is 14mm. On the D30 this will provide coverage equivalent to a 21mm lens. Not ultra-wide, but a lot wider than 28mm. There are three choices, all are 14mm and all have /2.8 maximum apertures. They are from Canon, Tamron and Sigma.
Normally my preference is to buy Canon's top-of-the-line lenses. These are optically excellent, very well built and as you might expect, quite expensive. The Canon 14mm f/2.8 retails for about USD $2,200. If I could see a number of years of regular use for this lens I would have bit the bullet. But, frankly, the Canon D30 is a transitional camera. By the Fall of 2001 Canon will be shipping its pro level digital body which will use a full-frame image sensor. My regular lenses will once again provide the full angular coverage that the good lord intended.
This means that any 14mm lens that I were to buy now would only see solid use for less than a year and then be relegated to specialized and occasional application. What to do? While saving money is an important consideration I wasn't willing to do so at the expense of image quality.
Choosing the Sigma
That left the two contenders to be evaluated Ñ the Sigma and the Tamron, ($800 and $1,100 respectively from B&H). In a review in 1999 by George Lepp in The Natural Image, (Vol. 15, #2) his evaluation of these three lenses was essentially that they provided similar resolution. All three needed to be stopped down considerably to provide completely even field coverage, as one might expect. The Canon had the best resistance to flare while all three provided decent rectilinear correction.
Photodo.com doesn't have a rating for the Canon 14mm but the MTF tests for the Tamron give it a 2.5 while the Sigma is rated significantly higher at 3.1. This is almost the same rating as given the Canon 17~35mm f/2.8L. (By way of comparison, the highly-regarded Leica Elmarit-R 24mm f/2.8 is also a 3.2)
One dealer had the Tamron in stock and a little while playing with it in the store left me unimpressed. Mechanically it just didn't feel or look terribly well made. It also has a rubbery finish that I don't care for. The Sigma, which I ended up ordering from B&H, is all metal and by comparison very substantial feeling. And, at $300 less than the Tamron and $1,400 less than the Canon seemed like a pretty good buy. The proof of course is in the images produced so let's see how it performs.
In the Field
My first opportunity to use this lens on assignment will be at the end of November on a shoot in central and northern Arizona. On my return around the second week of December I'll have a more complete feel for the lens and hopefully numerous real-world examples.
Till then these test shots taken in a local city ravine will have to do.
Photographed with Canon D30 at ISO 400. 1/60th sec @ f/11 with a Sigma 14mm f/2.8 lens. RAW Mode.
In these frames I'm looking for four things; resolution, contrast, coverage evenness and flare. Let's see how the Sigma works out.
The above photograph shows me several things. Resolution is, as expected, very good. In a large print small chips in the central concrete buttress are clearly visible. Contrast is fine and at f/11 at least there is no visible fall-off in the corners. The sun is out of the frame so flare isn't visible.
Left FrameÑ Photographed with Canon D30 at ISO 400.
1/125 sec @ f/16 with a Sigma 14mm f/2.8 lens. RAW Mode.
Right Frame Ñ Photographed with Canon D30 at ISO 400. 1/500 sec @ f/13 with a Sigma 14mm f/2.8 lens. RAW Mode.
These otherwise mundane shot are tests for flare. Wide angle lenses are very prone to flare when a specular highlight such as the sun is directly in the frame. Both of these frames have the sun just hidden behind a branch, but very much in the shot.
In the one on the left you can see a very small flare point on the left side of the path about a third of the way up. On the frame on the right with part of the sun directly in the frame there is hardly and flare at all, except just to the upper right of the sun. I regard these examples as showing excellent flare resistance. First class performance.
Photographed with Canon D30 at ISO 200. 1/125th sec @ f/8 with a Sigma 14mm f/2.8 lens. RAW Mode.
I'm looking for two things in this frame Ñ any sign of rectilinear distortion and also fall-off at the edges. Again, at this aperture at least, the field is quite flat, and as can be seen by the hydro pole at the extreme right of the frame there appears to be no distortion to speak off.
I like what I've seen so far. Construction of the lens is robust and it appears to work flawlessly with the D30, the EOS-1V and EOS-3. The D30 also "reads" the focal length for the information file, so clearly the Sigma know how to exchange full ROM data with the camera bodies.
The lens cap is well designed. Because the front element is so huge designing a protective lens cap can be an issue. Sigma has come up with a neat solution by providing a pressure-fit ring that first fits on the end of the lens, extending beyond the sculpted integrated lens shade. The standard lens cap then fits on the outside of this ring. Simple and effective.
Like all lenses of this type, as you can see from the photograph at the top of the page, the front element is exposed. This makes it susceptible to fingerprints and other more serious hazards so keeping the lens cap on when not actually shooting is probably a very good idea.
Initial impressions of this lens are very favourable. In a few weeks (early December) I'll update this report based on some real field experience while on assignment, and will undoubtedly have some additional comments as well as sample images.
Update: December, 2000
Photographed with a Canon EOS D30 and 14mm f/2.8 Sigma lens at ISO 100.
I have now returned from a week-long shoot in Indian Country. I ended up using the 14mm far more than I'd even anticipated and the results have been excellent. Please visit that report for additional comments.
Photographed with a Canon EOS D30 and 14mm f/2.8 Sigma lens at ISO 100.
The Sigma 14mm is now a tool that I feel that I can reply upon under almost any circumstances.
Strange as it may seem, for the first half year I only used the Sigma 14mm on my Canon D30, never on the EOS 1v. Consequently I never really saw the true edges of the frame. I recently did some tests comparing the Sigma 14mm with two other ultrawide angle lenses, the 12mm Heliar and the 30mm lens on the Hasselblad XPan. The results can be found in my review titled Battle of The Ultrawides.
While I have praised the lens in the review on this page I regret that my comments only apply to its use on a D30 or other digital SLR which doesn't show the true corners of the image circle. With a regular 35mm camera the results at the edges are not that great, and certainly not as good as the Heliar.
I have now purchased the new Canon 16-35mm f/2.8L lens and have done a comparison with the Sigma 14mm. The result is that while the Sigma continues to be an inexpensive solution for D60 and D30 owners, with film and with forthcoming full-frame DSLRs, the corner resolution on the Sigma will be found wanting.