This is a short review of the Sigma EX 15-30mm f3.5-4.5. I’ve had the lens for about two years now, and wanted to share what I mostly liked/ disliked most while using it.

Since it has been discontinued, this is one of the cheapest EX lenses that you can get second hand. I got mine for under $200 at a store where it was refurbished.

Overall, it’s my first choice lens for the sd14, because most of my photo’s are wide-angle or in the low tele range. Now, since the sd14 has a 1.7 crop factor, the lens range is the equivalent of 25.5-51mm on film. I’ve always liked the 50mm primes that camera’s used to default with, so that’s a good starting point on a general purpose lens. And at 25.5mm equivalent, the lens gives some more breathing room then the classic 28mm “wide angle” lenses. While this specific range is a personal preference, the lens does have many good qualities that would make it a good choice for walk-around lens.

I haven’t tried using it on a 35 film camera, but supposedly it is compatible. If that’s true, then the true 15-30mm range should result in some impressive photo’s.

The 15-30mm EX does deliver EXceptional quality in the center of the image. I will add some 100% crop examples of this later to illustrate. The corner sharpness leaves a lot to be desired. Especially on the wide angle range, corners become very blurry. But to be fair, that is only to be expected at this zoom range, especially for a lens priced this low. I don’t own other super wide lenses to compare this too, but reading other reviews it seemed that people believed the 15-30mm was one of the better performers out there.

Focusing is fast compared to a 18-200mm zoom I own. I’d say about three times faster. So while there may be faster lenses out there, the focus speed of the 15-30mm EX has always impressed me a lot.

You may have noticed that this is a pretty big lens. And sure enough it’s too large to fit some of my general purpose photography bags. But what you can’t see, is that at just over 600 grams it is very light for its size. As a result, the camera will face straight forward in most cases, when you hang it over your neck. So that is different from the 18-200mm for instance, which will drag the camera down and point at the ground, even with the lens contracted.

By default, this lens takes no filters. But here’s another things I’ve been lucky with. It turns out that some infra red filters have the exact same diameter as the large 82mm metal lens cap that comes with the 15-30mm EX. I was able to sort of jam it on there without any real effort. The filter I found, can’t be screwed onto a normal lens. It’s supposed to be attached with special clamps to any size lens under 82mm size, but hey. It automagically fit, so I never bothered with the clamps at all.

The one thing I don’t like is the clunky manual focus ring. The ring itself rotates smoothly, but switching between manual and automatic focus requires too much force. You have to pull the ring down until it clicks, to shoot manually, and push it back up to turn back to automatic again. Now, I used to often let the auto focus do most of the work and then switch to manual to fine-tune the focus. But with this lens, that is hard to do. Chances are that the focus gets messed up but the recoil of clicking the ring into place, so refocusing manually is more work then it should be.

And, well, there is this second thing that this lens has going against it. All sigma lenses are known to have a sort of yellow cast, and in my copy of the 15-30mm this is fairly strong. In many cases, this results in wonderfully warm images. But people with a dark skin tone always tend to look very yellowish when photographed with this lens. Although it may just be a combination of my particular copy of the ( refurbished ) lens and my particular version of the sd14.

Bottom line: the 15-30mm EX is sharp, light, balanced and fast. Hattori Hanzo would be proud.

UPDATE
I’ve tested the 15-30mm on a Canon AE-1, which will more or less fit Sigma Sa mount lenses. It not possible to actually click a Sigma Sa lens onto the Canon EF mount since the two are different of course, but the flange distance is the same and the lens will fit in place if you hold on to it to prevent it from falling out of the camera. The 15-30mm does not have a full coverage, so there is a circle around the picture. But the visible area is still pretty huge, much bigger then what is needed for an APS-C sized sensor. So you could fit the lens on a fill frame camera, cut away the black borders and still have a very, very large image left.