Pros & Cons
-
- Excellent resolution.
- Bright f/1.4 aperture.
- Minimal focus breathing.
- All-weather build.
- Fluorine coating.
- Available for multiple camera systems.
-
- Pricey.
- Heavy.
- Some barrel distortion and vignette.
- Doesn't focus as close as some others.
- No stabilization.
Sigma 40mm F1.4 DG HSM Art Specs
| Dimensions | 5.2 by 3.5 inches |
| Full-Frame Equivalent (Wide) | 40 |
| Mount | Canon EF |
| Mount | Leica L |
| Mount | Nikon F |
| Mount | Sigma SA |
| Mount | Sony E |
| Optical Stabilization | None |
| Weight | 2.6 |
Sigma's Art lens series has been a hit with photographers since its introduction. The concept is simple—bright lenses with excellent optics and reasonable prices. Many of its designs have been good enough to pass muster in the world of cinema, and Sigma has released those as part of its manual focus Cine series. The 40mm F1.4 DG HSM Art ($1,399)—an autofocus lens for SLRs and mirrorless cameras—puts optics designed for the Cine series into an Art lens, instead of going the other way around. Its optical quality is exceptional, but it's bulky and more expensive than others.
A Big Prime Lens
My first reaction to seeing the 40mm Art ($1,399.00 at B&H Photo Video) in person was to marvel at its size. It's a big lens. Not as big as a telezoom, but big when compared with other primes. It measures 5.2 by 3.5 inches (HD), weighs 2.6 pounds, and supports 82mm front filters. Compare that with the Sigma 35mm F1.4 DG HSM Art, which is much more typically sized (3.7 by 3.0 inches), lighter (1.5 pound), and has a smaller front element (67mm).
The 40mm has plenty of glass inside, which accounts for its weight and size. Its exterior is a mix of polycarbonate and metal, with the former making up the bulk of the barrel. Internal seals prevent dust and water from getting inside, and the exposed front element is coated with fluorine, a material that repels grease and moisture.
Sigma sells the lens in different versions for use with different camera systems. You can buy it in Canon EF, Nikon F, Sigma SA, Sony FE, or Leica/Sigma/Panasonic L. The versions for mirrorless systems are a couple of inches longer than those for SLRs, as the lens mount is extended to match the distance between the glass and image sensor across systems.
On-lens controls are minimal. There's no focus limiter or stabilization system, so the lone toggle switches between manual and autofocus. The manual focus ring is large and turns smoothly. It's covered in rubber, so you can grip it easily, even when wearing gloves.
There aren't a lot of bright prime lenses with optical stabilization, so it's not a surprise to see it missing from the 40mm. More full-frame cameras are getting in-body stabilization, which does a very good job with a moderate wide-angle lens like this one. If your camera doesn't have it, you can think about the Tamron SP 35mm f/1.8 Di VC USD or the Canon EF 35mm f/2 IS USM.
One aspect where the 40mm lags a bit behind competing lenses is in its close-up focus capability. The lens is able to focus as close as 15.7 inches (40cm), measured from the image sensor, for a maximum 1:6.5 life-size magnification. For most shots you won't have a problem, but you may find yourself leaning back to snap an image of a fancy plate, rather than leaning in. Competitors, notably the Tamron SP 35mm ($599.00 at Amazon) with 1:2.5 magnification, are a little more versatile for close-up work.
The truncated focus range may be a byproduct of the cinema-first design, which minimizes the change in angle of view when adjusting focus. It's something photographers don't have to think about, but is essential for professional-grade video work. Cinematographers don't want the frame to expand or contract when racking focus from one subject to another.
Excellent Resolution, Edge to Edge
I tested the 40mm Art in a Canon EF mount along with the 50MP 5DS R in the lab, and the EOS R and EOS RP in the field.
At f/1.4 the lens scores 3,942 lines on a center-weighted Imatest evaluation, which is just shy of the 4,000 lines we use as the cutoff for excellent resolution on the 5DS R sensor. The lens resolves fairly even resolution from center to edge, notching about 3,730 lines at the edges of the frame.
Similar Products
Our Current Picks for The Best Canon EF SLR Lenses for 2021
See How We Test Digital Cameras
Resolution ticks up to 4,194 lines at f/2, and edges keep up, showing close to 4,000 lines. The average score holds steady at f/2.8 and f/4, though edges tick up to approach 4,200 lines as well. The lens is at its absolute best at f/5.6, where it crosses over to outstanding territory with a 4,534-line score.
Image quality remains very strong at f/8 (4,398 lines). Diffraction sets in a little early when working with the 5DS R, so we see a big drop to 3,752 lines at f/11 and just 3,246 lines at the minimum f/16 aperture.
Resolution is higher than what we saw with the Sigma 35mm Art ($642.78 at Amazon) , which shows about 2,600 lines at f/1.4 but is competitive starting around f/4 (3,800 lines). Canon's EF 35mm f/1.4L II USM is more competitive with the 40mm Art in resolution at wide apertures, notching 3,448 lines at f/1.4, and is nearly a pound lighter, but costs a bit more and isn't an option for photographers working with other systems.
We also look at distortion when evaluating lenses. The 40mm shows about 1.4 percent barrel distortion, which gives straight lines a very modest outward curve. In-camera distortion corrections aren't typically available for third-party lenses, but it's a simple matter to remove when processing photos. Adobe Lightroom includes a profile for one-click distortion and vignette correction for this lens.
The lens shows a vignette effect at f/1.4 and f/2. Corners lag behind the center in illumination by about 2.4 f-stops (-2.4EV) when working wide open, and by about -1.6EV at f/2. Stopping down further brings the corner brightness within a stop of center, which is typically negligible in real-world use.
Premium Results, But Heavy
There is no question that the Sigma 40mm F1.4 DG HSM Art delivers exceptional image quality. It's a better lens than the company's lauded 35mm F1.4 Art, especially when partnered with a demanding, high-resolution image sensor, but it's also one that costs a lot more and, perhaps more importantly, is a good deal larger and heavier.
If you don't mind a heavy prime, the 40mm F1.4 delivers strong results, with crisp edge-to-edge resolution, even when shot at its brightest setting, which is no small feat. It's not perfectly corrected—there's a bit of distortion and vignette—but neither is offensive.
As good as the images from the 40mm Art are, I'm refraining from making awarding it an Editors' Choice award. Weight is a big factor; there's no reason not to reach for the 40mm if you're working in a photo studio or on a soundstage, but it's another matter to think about packing it in your bag for a trip or to take it out on a hike. Your mileage may vary, of course, and if you're shopping for a moderately wide prime, you won't find many lenses that are technically better than the 40mm F1.4. If you're more sensitive to price, or bulk, think about the Sigma 35mm F1.4 Art or Tamron SP 35mm F1.8 Di VC USD as alternatives.
Best Lens Picks
- The Best Fujifilm Lenses for 2020
- The Best Leica M Lenses for 2020
- The Best Micro Four Thirds Lenses for 2020
- The Best Pentax SLR Lenses for 2020
- More Lens Reviews
- More from Sigma