The Sigma 40mm f/1.4 Art is such a ridiculous lens. Whenever I've thought about 40mm lenses I thought about the Canon EF 40mm f/2.8 pancake lens. I'm sure many of us have owned one of these lenses; it's actually pretty good. The tiny form factor, relatively fast autofocus speeds, and great image quality. Obviously, this lens was just too small for Sigma.
As a company, Sigma is known for producing somewhat irregular or relatively unique lenses. They're not afraid of making huge heavy lenses with super wide apertures. Lenses like the 14mm f/1.8 Art, and fast aperture zoom lenses like the 24-35mm f/2.0 Art and my favorite APS-C lens, the 18-35mm f/1.8 Art. All of these lenses have one thing in common, they're huge. The latest addition to Sigmas lineup is the 40mm f/1.4 Art lens. This one really takes the cake. I'm not even sure how they've managed to make this mid-range focal lens into the behemoth that is it. I mean it weighs more than the Sigma 85mm f/1.4 Art.
How is that even possible?
Sigma Struggles to Make Small Lenses
Ok, so, the above subheading may be a little provocative but, at least it's not clickbait right? Here's the thing though, if you compare almost any Sigma art lens to any other manufacturer, Sigma is generally significantly larger and heavier. Take the Nikon 105mm f/1.4 lens for instance. The Nikon version is an incredible lens with both super sharp results wide open and beautiful bokeh. Sure, the Sigma 105 f/1.4 Art is better when it comes to optical performance but it's only really noticeable on test charts. The weight and size differences are very real and very noticeable. The Sigma is heavy even when it comes to medium format lenses. The 105mm from Sigma is about as heavy as the Schnieder Kreuznach 150mm LS f/2.8 and actually has a larger filter thread size. The weird thing is that even with the much larger front element, vignetting isn't much better when compared to the Nikon lens. Aside from being slightly sharper, why is the Sigma lens so ridiculously huge?
Another lens that comes to mind is the 85mm f/1.4 Art. Compare that to some of the other alternatives available from Canon and Sony you'll see a similar pattern. Sharpness wide open is slightly better but other than that it doesn't offer any significant advantages. Even with the huge size and massive front element, the lens still has a pretty poor T-stop rating at T/1.8. That's the same T-stop values as the Sony 85mm f/1.8 Batis. I should mention the fact that the vignetting is noticeably better than the Sony 85mm f/1.4 GM even if the T-stop isn't. I guess for this lens the front element is helping.
More recently Sigma released their 40mm f/1.4 Art lens. A recent review from Kai Wong demonstrates just how huge and almost unwieldy this lens actually is. I get that it is a super sharp lens, even when compared to high-end performers like the Canon 35mm f/1.4 II. This lens might even be the sharpest lens Sigma has ever produced and that's really saying something. Although, at 1.2kg it's such an impractical, ridiculous lens that I wonder why anyone would actually want it. This is especially evident when you consider the significantly smaller and lighter alternatives like almost any 35mm f/1.4 or 50mm f/1.4 lenses.
The point I'm trying to make is that for one reason or another Sigma seems to struggle when it comes to producing fast aperture lenses that aren't beyond practicalities. Sigma seems to love having a huge front element in their lenses. In my discussions with Sigma, they explained how the larger front element helps to prevent vignetting. I could be wrong here but surely, using a camera profile would be far more efficient, wouldn't it? Even with the same focal lengths compared to other manufacturers, Sigma prioritizes sharpness over everything else. This includes important aspects such as T-stop values and the weight/size of their lenses balloons to a point where it's just silly.
I've Stopped Shooting With My Sigma Lenses
For the last year, I haven't used any of my Sigma lenses for any professional work. Aside from a few comparisons I've done where I needed to shoot with them, I haven't even used them for any of my personal work. This isn't intentional by any means it's just that I'm reluctant to use my Art lenses for any work I have.
They take up too much space in the bag, they weigh far too much and comparatively speaking they don't offer that much better quality compared to some other lenses I have. Lenses like the Batis 85mm or the Sony Zeiss 55mm f/1.8 which are tiny in comparison and offer fantastic image quality unless you're being super pedantic about the finer details. I honestly care more about my back than having slightly better image quality that no one will actually notice. Why would I want to suffer so much for so little? Speaking of image quality, looking at the images below, is there really that much of a difference in sharpness? One was with the Batis 85mm and the other with the Sigma 85mm Art on the Sony a7R III, both were shot wide open.
The difference in size is significant
When I first bought lenses like the Sigma 85mm Art, I actually boasted about how huge it was. The feeling I had was almost like "yes this is what professional use" which is obviously nonsense. Having a huge lens with a massive front element is somewhat pleasing for the ego, some could describe it as overcompensating. Ultimately, I find that I don't use my Sigma lenses as much as some other lenses I now own and it's purely because Art lenses are mostly impractical.
In Defense Of Sigma
My assumptions are that Sigma uses large optics because that's probably one of the most effective ways to produce super sharp high-resolution lenses. It would seem as though smaller optics may not be able to produce the same level of detail for a number of reasons. It may go to explain why so many medium format lenses are so much better optically speaking and Sigma is using that method to produce full frame lenses. There's obviously a large market of photographers who want very high-quality lenses and don't mind the extra weight and size. If you need the absolute best in quality, then you may have to compromise in areas of practicality.
Unfortunately, there isn't a perfect option and Sigma now caters to a certain section of the market that tends to appreciate quality over some practicalities. This is also one of the reasons I won't be selling my Sigma Art lenses anytime soon because there are instances where I need that level of quality. It's rare but I like the idea that I can offer then when required. Sigma has produced some incredible lenses and I'm honestly a huge fan. Being a fan, however, doesn't mean I won't point out some of the aspects I dislike or consider to be rather ridiculous. The 40mm f/1.4 Art is definitely a ridiculous lens and right now I'm struggling to understand how it could ever be a popular option.