Sigma 50mm f1.4 DG DN Art review
Written by Gordon Laing
The Sigma 50mm f1.4 DG DN Art is a standard prime lens designed for full-frame mirrorless cameras and ideal for general-purpose use. At the time I made this review, it was available for Sony e and Leica L mounts, the latter working on Panasonic Lumix S bodies.
Announced in February 2023, the 50mm f1.4 DG DN becomes the fifth dedicated mirrorless lens in Sigma’s high-end Art series, sandwiched between the existing 20, 24, 35 and 85 models, all sharing the same fast f1.4 aperture.
In Sigma’s World, DG means corrected for full-frame sensors, DC means corrected for cropped / APSC sensors, and DN means designed for mirrorless cameras only. So this new DG DN lens is not compatible with DSLRs, but the earlier 50mm f1.4 DG HSM Art is still available for a variety of DSLRs at a roughly similar price, and can also be successfully adapted to most mirrorless systems if desired. In my complete review below I’ll show you everything the new DG DN lens can do, but if you prefer to read the highlights, keep scrolling!
In terms of competition, the Sony e-mount isn’t short of native lenses in the 50mm focal length or thereabouts, available in a huge range from Sony’s own budget f1.8 costing $250 to their premium f1.2 G Master at around two grand.
Sitting roughly in the middle are a pair of f1.4 models: one from Samyang at around $750 and the other a Sony / Zeiss collaboration from 2017 which still sells for up to $1500 but which I’d expect will be updated at some point. And don’t forget the satisfyingly compact Zeiss 55 1.8 either which helped launch the system.
In the L-mount, there’s Panasonic’s slightly dimmer 50mm f1.8 costing around $450 and the high-end f1.4 Pro version at around $2000. Leica also has a 50 1.4 for L-mount, but at around $6500 it’s not really a contender here.
So the Sigma 50 1.4 Art slots comfortably between existing budget and premium options for both mounts, hopefully delivering a taste of the high-end without breaking the bank. Let’s find out if it lives up to its promise, not to mention the excellent reputation of its older sibling for DSLRs.
Starting with the design, the 50 1.4 Art measures 78mm in diameter, 110mm long and weighs 670g, making it smaller and lighter than the old 50 1.4 ART lens for DSLRs.
In your hands it feels solid and well-built, with Sigma claiming dust and splash resistance including a water and oil-repellant coating on the front element and a rubber seal at the mount-end.
It’s styled like other recent Sigma lenses, starting with a manual aperture ring, here from f1.4 to f16 in third-stop increments with an A position for body-based control if preferred.
Alongside the aperture ring are a switch for manual focus, a customisable autofocus Lock button and a switch to declick the aperture ring for smooth and silent adjustment. Round the other side is another switch to lock the aperture ring at the A position if desired.
Occupying roughly the outer half of the barrel is a ribbed manual focusing ring which, like Sigma’s previous DG DN models, feels smooth and more damped in operation compared to the looser style of Sony’s own lenses.
At the end of the barrel is a 72mm filter thread and Sigma supplies a bayonet petal-shaped hood as well as a padded carrying case.
Let’s now check out the autofocus, and I made all my tests here using an e-mount version mounted on a Sony A7 IV body. Here in Single AFS mode, you can see the operation is pretty quick, albeit with an occasional wobble to confirm.
This is standard-practice for Sigma lenses in AFS mode though, and if you switch to Continuous AFC, you’ll enjoy a boost in confidence thanks to the phase-detect system used by Sony in this mode. Now by avoiding any overshooting, it’s faster than before.
Here’s the same test for video, again at f1.4 and filming in 4k 25p. Sony uses AFC for video, so the focus pulls are smooth and accurate here with no overshooting.
Single autofocus pulls are easy though, so here’s the Sigma and Sony pairing with face and eye detection using the full AF area, and again with the lens full-opened to f1.4.
Here you can not only see how the body drives the lens to keep me sharp at all times, but also the potential for blurring in the background when you’re filming pieces to camera. I’ll have a stills portrait test later in the video.
Next for focus breathing where I’ll manually focus the lens from infinity to the closest distance and back again. As I focus closer, you’ll see the effect of breathing where the image becomes more magnified, almost like a zoom lens.
It’s not a problem if you’re shooting stills, but can become distracting when filming video. The effect is certainly pretty strong here when focusing between the extremes and sadly Sony’s compensation on recent bodies won’t apply to third party lenses.
That said, when performing more modest focus pulls, such as those in my bottle or face tracking tests, the effect is reduced and may not be an issue. Only you can decide if this is an issue for you or not.
Speaking of compensation, the 1.4 Art, like all of Sigma’s DG DN lenses, is designed to be used with lens profiles to correct for geometric distortion. If you’re using a Sony body, you’ll want to set Distortion Comp to Auto in the Lens Comp menu, and that’s what I’ve used for all my optical tests here.
But for the optical enthusiasts out there, I’ll briefly show you versions of Brighton Pier with Distortion Comp toggling between Off and Auto. As always, the Auto option will result in a crop in order to apply the correction, the degree of which depends on the lens in question, but here it’s pretty mild and what you’re left with in Auto is only fractionally less than other 50’s I’ve tested. I certainly wouldn’t worry about it.
Ok, so let’s now angle that view so that details run into the corners, and once again all of my images going forward have Distortion Comp set to Auto as the lens is designed to be used. Here the Sigma is wide-open at f1.4, and as always in this test I’ve focused on the middle of the image.
Taking a closer look at the centre of the frame reveals the lens performing well out of the gate with crisp details. Closing the aperture to f2 and 2.8 brought a mild boost in contrast here, but I’d certainly be happy using the lens wide-open when the subject is in the middle. But what about the corners?
Let’s return to the f1.4 frame and head out towards the extremes where you’ll notice darkening due to vignetting – not unusual for a large aperture lens – but at least the details remain pretty respectable.
Gradually closing the aperture lifts the vignette and it’s essentially gone by f2.8 to f5.6, but I’d say the corner sharpness remains just about the same and looks pretty good wide-open. So for landscape views, I’d be aiming to use the lens at around f4 to f5.6 for the best overall results across the image.
Since I was focused in the middle of the frame, it also indicates the field is fairly flat. Obviously if your main subject is in the corner, you’d focus there instead.
50mm lenses are a popular choice for close-range portraits or smaller group shots, and while they lack the compression and isolation of longer focal lengths, some prefer their more engaging perspective, while a fast f1.4 aperture can still deliver significant blurring in the background.
You’ve already seen the 50 1.4 Art in action for video earlier, so here it is for a stills portrait, where it’s clear the degree of blurring you can achieve at f1.4 even when the background’s only a few meters distant.
Zooming-in for a closer look reveals crisp details on my face within the very shallow depth of field, with a rapid fall-off to blurring on either side of it. Meanwhile the rendering in the background looks smooth without any distracting busy-ness.
Of course at 50mm f1.4 from a portrait distance, the subject’s nose and ears will fall out of the depth of field and become blurred, so here’s how the portrait looks with the aperture closed two stops to f2.8. Now more of my face is in focus, with crisper details and without losing too much blurring behind me.
And now closed one more stop to f4 where the greater depth of field has rendered more of my head in focus, and while more of the background is now discernable, I’d say the rendering is remaining well-behaved.
For a closer look at the potential for bokeh and rendering, here’s my ornament test, where I’ve positioned the lens near to its minimum focusing distance. You’re looking at the lens with its aperture fully opened to f1.4 here where the fairly lights are transformed into large bokeh blobs with fairly soft edges and only the slightest hint of textures within if you’re looking really closely.
Like most large aperture lenses, the blobs become elongated rugby ball shapes towards the corners, but become more circular as the aperture is closed, here one stop at a time.
As this progresses, the impact of the 11-bladed diaphragm system can be seen a little in the shape of the blobs, but I’d say it’s pretty subtle here with no obvious hard angles.
More importantly, as the aperture is closed and more of the fireplace becomes visible, I’d say the Sigma lens is rendering the view very nicely, certainly up to f8.
If you’re looking for bokeh blobs at more of a portrait distance, the Sigma has you covered. Here’s another face-tracking video, but this time indoors with the lights behind me rendered into attractive blobs. This is going to be a nice lens for presenting pieces to camera from a tripod as well as for traditional portrait photography.
Sigma quotes a closest focusing distance of 45cm for the lens, but I always check the performance at the minimum distance by simply photographing a ruler as close as I can manually focus on it. This is the result at f1.4 where I could reproduce a subject measuring 192mm across the width of the frame.
Taking a closer look at the edge, you’ll see the image becomes soft with the aperture wide-open from this distance, but closing it down to f8 here has delivered a crisp result across the frame.
Just before wrapping-up, I wanted to show a couple of shots where I deliberately tried to trigger lateral chromatic aberrations with high contrast subjects against a strongly backlit sky. I shot these at f1.4 to show the effect at the maximum aperture.
If you look closely enough, you might see a hint of coloured fringing in the toughest areas, but to be honest it hardly stood out and I was really looking for it. Of course your mileage may vary in all the tests I’ve made, but certainly the 50 1.4 DG DN Art isn’t a bad offender by any means, even when focused as close as possible.Check prices on the Sigma 50mm f1.4 DG DN Art at B&H, Adorama, WEX UK or Calumet.de. Alternatively get yourself a copy of my In Camera book, an official Cameralabs T-shirt or mug, or treat me to a coffee! Thanks!