Sigma 24mm f2 DG DN review
Written by Gordon Laing
The Sigma 24mm f2 DG DN is a wide-angle prime lens for full-frame mirrorless cameras that costs around $650 or 550 British pounds – and at the time I made this review, available in Sony-e and Leica-L mounts, but if we all wish at the same time, maybe coming to Canon RF and Nikon Z mounts in the future. Sigma loaned me a pre-production sample in the e-mount to try out and you can see how it performs in my full video review below! Alternatively if you prefer to read the written highlights, keep scrolling!
Announced in September 2021, the 24mm f2 joins Sigma’s growing I series of compact full-frame mirrorless lenses. Here’s the existing 35mm f2 DG DN in the middle with the new 24mm f2 on the left and the equally new 90mm f2.8 on the right that was launched alongside the 24 f2 – and I’ve reviewed that one too. Add the previous 65mm f2, 45mm f2.8 and 24mm f3.5 and you have six models in the series to choose from.
This means Sigma now has two 24mm lenses in this series, with the smaller, lighter and slightly cheaper f3.5 version seen here launched just nine months earlier. Sony also has a compact 24mm f2.8 seen here launched in March 2021, and there’s also faster f1.4 models from both companies as well as an older f2.8 option from Tamron. In this review I’ll show you how the Sigma 24 f2 performs to help you make the right choice.
At 70x72mm and weighing 365g, the Sigma 24 f2 is unsurprisingly larger and heavier than either the 24mm f3.5 or the Sony 24 2.8, but considering the faster aperture it’s still fairly compact, and the aluminium body feels reassuringly well-built. Like other models in the series, there’s weather sealing at the mount with a rubber grommet, but not throughout the barrel.
In terms of controls there’s a chunky switch for auto and manual focus, a clicky aperture ring from f2 to f22 in one third increments and an A position for body control, and a narrow but smooth and nicely-damped manual focusing ring. Unlike Sony’s recent lenses, there’s no custom button nor de-clickable aperture ring option.
Like other models in the I series, Sigma supplies not one but two lens caps, so as well as the usual spring-loaded plastic cap, there’s an additional metal disc which attaches magnetically, with a satisfying snap and the magnet feels strong enough to keep it in place too. With the hood mounted though, this second cap is a little awkward to fit or remove, so it’s arguably a bit of a novelty, but I like that Sigma’s trying something different here.
At this price point, you might expect a basic plastic hood, but Sigma supplies its I series with aluminium hoods that continue the ribbed style of the lenses for a classy vintage look and feel. I really like the way these lenses look.
Ok, let’s check out the focusing speed and for all my tests in this review I used a Sony A7 III as it was the best body I had access to at this time. You’re looking at Single AFS mode where as usual there can be a minor contrast-based wobble to confirm, but it’s still swift. And for reference here it is again in Continuous AFC mode, where the phase-detect system avoids the wobble.
Here’s the same test for video with the A7 III filming in 4k and the 24mm at f2 and using continuous AF to pull focus between the bottles smoothly and confidently; it’s very quiet too.
Next for a face detection test with the Sigma 24 f2, again for movies in continuous AF, with Wide area and human eye detection enabled. The 24mm focal length may not be your first choice for portraiture, but if the subject’s positioned carefully it can work for environmental compositions where you see more of the surroundings.
Sticking with this scene, here’s a still portrait shot at f2 where there’s some nice separation from the background. Looking closely also reveals nice sharp details around my eyes even with the aperture wide-open.
For comparison here’s the Sony 24mm f2.8 from my earlier review and now the Sigma 24 f3.5, showing progressively less blurring behind me due to the smaller apertures. Side by side you can see the Sigma 24mm f2 on the left is delivering visibly greater separation and for me, by far the most attractive background rendering of the three.
Next for the rendering of bokeh balls from close range, with the Sigma 24 f2 near to its closest focusing distance, starting wide-open at f2 and gradually closing down in one stop increments. At the maximum aperture the blobs take on cat’s eye shape towards the corner, but become mostly circular at f2.8. Taking a closer look back at f2, you’ll see some outlining and faint textures within the blobs, which isn’t ideal, but unsurprising for a lower-priced lens. If you want cleaner – and larger bokeh blobs – aim for one of the 1.4 versions. Side by side with the Sony 24mm f2.8 in the middle and the Sigma 24 3.5 on the right though and while the angle is a little different, you can see how much nicer the rendering is from the Sigma f2 on the left.
Before moving on, Sigma quotes a minimum focusing distance of 24.5cm. I photographed this ruler as close as the lens would actually focus, where the subject measured 193mm across the width of the frame.
Before my distant landscape comparison, a quick look at geometric distortion starting with the Sigma 24mm f2 with Distortion Compensation on the Sony A7 III set to OFF, which is the default. With this setting, the Sigma lens exhibited quite strong barrel distortion, so for my in-camera JPEG tests, I changed this setting to Auto where you can see the distortion becomes much better-corrected with only a minor crop to the field of view. You can also apply it in post to RAW files.
So here’s my distant landscape view with the 24mm f2 angled as always so that fine details reached right into the corners. First with Distortion Compensation set to OFF and now with it set to Auto where you can see the correction in action. This was at f11, so now let’s switch to the f2 version where you can see straightaway the usual darkening in the corners due to vignetting – something that’s easily corrected. Taking a closer look in the middle of the frame reveals fine details right out of the gate at f2. In my tests closing the aperture improved the contrast a little but didn’t make any visible difference to sharpness in the middle. Heading out into the far corner and you’ll see the darkening due to vignetting, but the details still look respectably sharp even with the aperture wide-open. As you close the aperture, the darkening lifts and there’s arguably a small improvement in ultimate crispness, but overall I’d say this lens is performing very well across the frame even wide-open. Comparing it to my earlier results from the Sony 24 2.8 and Sigma 24 3.5 shows the f2 model can keep up with them on distant sharpness even with the larger aperture.
Oh and if you’re looking for sunstars, here’s what you can achieve with the Sigma 24mm f2 closed all the way to f22. Here’s another example at f22, this time filming video where the Sun’s peaking in and out from behind leaves and branches.
Just before wrapping-up, a few more comments for videographers. 24mm is a nice focal length for handheld vlogging, and you can see it here at f2 using IBIS only on the A7 III. There’s much nicer subject separation than the Sony 2.8 and Sigma 3.5 models, although like all 24mm lenses the view can be a little too tight.
If you prefer a wider view, how about the Samyang 18mm f2.8 seen here at f2.8. It’s a really nice option for Sony vloggers who want a small, light and affordable wide prime, but you will of course miss out on the potential for blurring, plus the greater crispness of the Sigma.
And finally, a focus breathing test with the Sigma 24mm f2 starting at infinity and gradually focusing manually to the closest distance and back again. Just like the 3.5 version, the field of view reduces here as you focus closer, although interestingly on the Sony 2.8 model it actually widens a little as you focus closer. Is it a big deal for videographers? Here I am moving closer or further from the camera where you can see the overall coverage varying a little. Not ideal, but probably not deal-breaking for the target audience.Check prices on the Sigma 24mm f2 DG DN at B&H, Adorama, WEX UK or Calumet.de. Alternatively get yourself a copy of my In Camera book or treat me to a coffee! Thanks!