Hands-On Review: Sigma 45mm f/2.8 DG DN Contemporary Lens

Hands-On Review: Sigma 45mm f/2.8 DG DN Contemporary Lens

The Sigma 45mm f/2.8 DG DN Contemporary, long awaited and highly anticipated, is a newly developed native lens for full-frame mirrorless cameras. Among the initial trio of lenses recently announced, this is perhaps the sleeper hit of the group and, while it has fewer eye-catching specs, such as an f/1.2 maximum aperture or a wide-angle zoom range, this 45mm f/2.8 excels in more practical ways. It’s a much more modest lens with sneaky good performance, and since it’s “just” an f/2.8 lens, it’s also noticeably smaller and lighter in weight than most popular ultra-fast prime lenses. For me, this is the calling card of the lens, and something that shouldn’t be overlooked or undervalued, especially considering the recent trend of camera sizes increasing.

I had the chance to take the new 45mm f/2.8 for a recent trip to upstate New York, and paired it with the newly announced Sony a7R IV. Even though I shot with and will be speaking about my experiences with an E-mount version of this lens, I want to point out quickly that this lens is also available for the Leica L mount. And this is a big deal, because these three lenses are Sigma’s first releases as part of the L-Mount Alliance. The L-mount version of this lens will be compatible with Panasonic and Leica full-frame mirrorless cameras, and will also be compatible with Sigma’s forthcoming L-mount mirrorless bodies. At the moment, this lens is the smallest autofocusing lens available for L-mount cameras; hopefully signaling more good things to come.

But, back to the Sony E version… the combination of this lens and the new Sony a7R IV body was one of the better matches I can remember in a while. The a7R IV is a good bit chunkier than previous a7 cameras, and has a more ergonomic grip and, with this sleek lens, it felt like a perfect combo for a weekend of walkaround shooting. The 45mm focal length also contributes to this feeling, of course. It’s been a bit of a trend lately, but seeing more brands produce lenses between 35mm and 50mm feels good. In my mind, it’s the perfect focal length for silencing the debate about 35mm versus 50mm—it’s a bit wider than a 50mm, so it feels natural; it’s a bit narrower than a 35mm, so it feels more selective and intentional. 

Then there is the f/2.8 maximum aperture that I mentioned briefly, above. I, for one, am really excited about this decision from Sigma, to make a slower lens that consequently means a smaller lens. I’m a big fan, along with many others, of the Art series primes from the last few years, but the no-holds-barred attitude when designing those results in notably large and heavy designs. Most of the time, I don’t need an f/1.4 lens. As much as I may want it, I really don’t need it. On the other hand, most of the time I want a smaller lens design, and sometimes I do really need it for the cases when I’m traveling to shoot and portability is key. Another reason the choice for f/2.8 doesn’t phase me is that camera and sensor technology has gotten so good, that I’m no longer as wary of shooting handheld at 1/30-second or bumping up to ISO 6400 or so. With improved sensor designs and sensor-shift image stabilization, low-light shooting is no longer relegated to ultra-fast primes.

Delving a bit deeper into the technology of this lens, Sigma used a pair of aspherical elements to realize sharp, crisp image quality that also renders imagery with geometric accuracy and no perceivable distortion. The Super Multi-Layer Coating is also adept at cutting flare and provides really nice color balance with high saturation and contrast. I was impressed by the color, tones, and consistency this lens provided in all lighting conditions. Also tech-related, this lens has a stepping motor to provide fast and quiet autofocus performance, suitable for stills and video. I had no complaints about focusing speed or accuracy with this lens—it’s quiet, it worked, and it worked quickly. It’s such a small lens, focusing shouldn’t really be a big issue, anyway.

In another nod to modesty, this lens has a rounded seven-blade diaphragm. It’s not nine, not 11, not some other crazy number; there are seven blades and they still render a smooth quality to out-of-focus features in shallow depth of field images taken at mid-aperture. Sigma goes on about the “beautiful bokeh” this lens renders, stating that “this lens softens the periphery of blurred images suppressing the double-line bokeh… and enhances the three-dimensional impression of the subject with the smooth expressions in the foreground and background.” I certainly have no arguments about a statement like that, after using this lens, but it’s also a long-winded way of saying that the rendering of this lens is impressive, and it handles focus falloff smoothly. Also playing into all this talk about bokeh, this lens sports a minimum focusing distance of just 9.4", which yields a 1:4 maximum magnification ratio. This is quite nice with a normal-length prime, and makes it a suitable choice for some more casual close-up shooting.

Finally, I want to talk a bit about the physical design of this lens, because that’s one of the main selling points of a lens like this. It’s what I wrote about at the beginning, in reference to it being quite compact, which became an even more impressive feat to me after seeing the resulting image quality. In typical Sigma fashion, the finish of the lens feels and looks great. Contrasting many of the Art primes, though, this lens apparently does not use Sigma’s Thermally Stable Composite (TSC) material, instead opting for an aluminum lens barrel for “improved durability.” Complementing this design is the included metal bayonet lens hood, which is knurled on the exterior to make it easier to remove or install. The lens mount is brass and there is weather sealing at the mount end of the lens, which helps to keep dust and water out. Another unique trait of this lens, versus other Sigma Global Vision lenses, is the inclusion of a manual aperture ring. It can be set to “A” position if you still want to use your camera to change settings, but the aperture ring is a nice throwback and the click stops have a nice tactility. Also worth noting, the torque of the manual focus ring is great on this lens, considering it’s a focus-by-wire design.

I was sad to give back the lens after only using it for a few days. It’s the type of lens that excites me most since it is so practical and pragmatic, but not lacking on any valuable front. You’ll notice I’m often comparing or relating this lens’s attributes to Sigma’s Art series throughout this article, but I didn’t necessarily note that this is a Contemporary series lens. The reason I did this is because I truly felt like the quality of this lens more resembled that of an Art lens than my former impressions of their Contemporary series. The only distinguishing feature that keeps this 45mm f/2.8 from being considered an Art prime, in my mind, must be the f/2.8 design… which, in the end, is something I consider one of its strengths.

What are your initial impressions with Sigma’s first native lenses for full-frame mirrorless cameras? How do you feel about opting for a slower f/2.8 design? Which lens would you like to see next from Sigma? Let us know your thoughts in the Comments section, below.


I recently bought this lens as a substitute to the 50mm art which I’d been using for many years on both Canon and Nikon DSLR bodies. I hadn’t fully appreciated the size and weight until I tried the Sony (a7r iii) mount version. I needed something smaller that wasn’t going to compromise much on image quality.

The Sigma 45mm was an interesting consideration. I initially wondered about such a ‘slow’ aperture until I looked up what apertures I’d been using on the 50mm art (Lightroom can be very useful here). It seems that I’d hardly ever used it at it’s maximum aperture! I tend to stop down a little by habit.
So it was down to image quality. I was in a brief position to own both lenses to compare both in my studio and outside.
I’d have to say that the image quality is right up there with it’s 50mm brother. I’d even go as far to say slightly better. It will focus closer than the 50 but does suffer from softness when too close. Stopping down to f4 works well. This isn’t designed for close up photography and the lower image quality is quite normal (wide open). Increase the distance a little and I’d be quite happy shooting at f2.8.

The build quality is very high. It has a traditional feel to it (even Zeiss like, dare I say!). The metal lens hood is superb.
Handling is good but not without issues. The focus ring is beautifully smooth and has just the right amount of torque; I actually forget it’s focus by wire, it’s that good on the a7r iii! The only thing that is a bit fiddly is the position of the focus ring and it’s modest width. It sits too close to the lens hood and you can’t help touching the hood whilst focusing. This is more a a minor irritant than a deal breaker but it’s a shame nonetheless.

The aperture ring is a pleasure to use too. It feels high quality and it’s tactile nature is reminiscent of a film camera lens. Having said that you do have the choice of controlling the aperture though the camera which is a nice touch.
I’m so glad I gave the 45mm a try. It’s image quality is very high and the size and weight are perfect for the a7 series bodies. F2 might have been nice but the size, weight and cost would have increased. As it is, it’s a well considered fine balance between practical and quality.

All good points, Dayve. That's a good suggestion, to check through previous shots to see how often you use apertures wider than f/2.8 to determine how this lens would fit into your workflow. Hope you enjoy the 45mm, it's been one of my favorite lenses I've used in a while.

Hi Bjorn, Thanks. I’m looking forward to working with the Sigma very much!