As an adventure photographer, a fast wide angle lens is one of my favorite tools. The Sony 20mm f/1.8 is my current number one choice.
Whether shooting astrophotography or action images, the utility of a wide angle lens with a fast aperture is essential.
It becomes even more useful when it’s in such a lightweight, compact package, typical of the latest range of f/1.8 lenses from Sony.
Prior to the release of this lens, there weren’t many options for a compact, wide, fast lens.
I’d been hoping Sony would release a 20mm fast lens, but this one has exceeded my expectations.
Read on below for why I think this is one of the most useful lenses Sony has recently released.
Table of Contents
Sony 20mm f/1.8 Specs
- Corner-to-corner sharpness
- Compact size
- Light weight
- Rugged and durable
- Slightly expensive
- Sony E-Mount/Full Frame Lens
- Aperture Range: f/1.8 – f/22
- Minimum Focus Distance: 2.62′ / 80 cm
- Weight: 1.32 lb / 602 g
- Length: 3.3″ / 85 mm
- Diameter: 2.2″ / 74 mm
- Filter size: 67mm
Build & Ergonomics
From my past experience with Sony lenses, build quality is typically quite good. The Sony 20mm f/1.8 is no exception.
The mostly metal body of this lens feels rugged and durable. Although it’s only rated as a “G” lens, as opposed to Sony’s highest-rated “G-Master” or “GM” lenses, it feels equally well built.
This lens is fully featured with a manual metal aperture ring, auto/manual focus switch, de-click switch for silent aperture adjustment, focus hold button, and smooth manual focus ring.
Rubberized grips on the aperture and focus ring provide a firm grip when handling the Sony 20mm f/1.8. This is a welcome feature since some of the older Sony lenses tend to be a bit slippery with all-metal exteriors.
In the design of this lens, it appears no features were left out, making the price more justifiable – more on that later.
Fast-focusing is now the norm with all the latest Sony cameras and lenses. The Sony 20mm f/1.8 is no exception and I never have any issues with focusing.
It locks on to and tracks objects extremely quickly. In addition to quick focusing, this lens does quite well in very low light.
The fast aperture of this lens combined with cameras like the a7 III (or, even better, the a7S III) makes it very effective at focusing in near darkness.
Although this is only a G lens (instead of GM or G-Master) it focuses equally as well as my other GM lenses. (Read on below for more info on GM vs G when it comes to image quality.)
The other thing to consider is that wide-angle lenses inherently make focusing easier because of hyperfocal distance calculations.
Basically, the wider the lens, the more of the scene will be in focus. Telephoto lenses, on the other hand, have to work much harder to achieve focus.
This formula means that if you focus on something a few feet away with a wide-angle lens like the Sony 20mm f/1.8, everything in the frame will be sharp.
Using the PhotoPills Hyperfocal calculator, this lens at f/4 will be sharp from about 5ft (1.5m) to infinity if you focus on a subject 12 ft (3.6m) away.
In summary, the autofocus on this lens is superb and won’t slow you down or cause blurry images.
The Sony 20mm f/1.8 has become one of my favorite lenses because of the quality it offers.
I love shooting wide-angle scenes, and a lens that delivers edge-to-edge sharpness with minimal distortion, vignetting or other issues is a welcome addition to my kit.
As I mentioned above, this lens is only rated as a G lens instead of a GM or Gold Master lens. In this case, I think the rating is actually an advantage because you get near GM quality without GM prices.
When I compared this lens to other GM lenses I’ve used, I can’t tell the difference in quality when it comes to sharpness or croma.
The Sony 20mm f/1.8 is very well controlled when it comes to chromatic aberration and distortion. The slight vignette is easily removed when the lens correction profile is applied in editing software.
Bokeh with wide-angle lenses isn’t really a concern for me since I rarely shoot subjects close enough to get bokeh with a 20mm lens.
At f/1.8, this lens will blur the background nicely if you focus on very close subjects (less than 3ft / 1m) but the distorted representation of objects this close to a wide-angle lens isn’t very flattering.
You can minimize this effect by keeping subjects away from the edges of the frame, but it’s still not the most pleasing to the eye (in my opinion).
The bottom line when it comes to image quality on the Sony 20mm f/1.8 is that it gives a really nice image. The color, contrast, and sharpness are very pleasing and surpass the quality I was hoping for with this lens.
Sony 20mm f/1.8 Sample Images
Here are some sample images taken with the Sony 20mm f/1.8, using a Sony a7 III (reviewed here).
Value for Money
At around US$850, this lens isn’t cheap – but you get what you pay for. The quality and features it offers are well worth the price.
There are a few alternatives to the Sony 20mm f/1.8, but none of them strikes the perfect balance of quality and features.
The Tamron 2omm f/2.8 is much cheaper but doesn’t offer nearly as fast an aperture. The Tokina 20mm f/2 is very similar but you don’t get features like the focus hold button or the manual aperture ring.
Another lens that people will likely be considering is the Sony 24mm f/1.4 GM lens but it’s more than $500 more expensive and doesn’t offer as wide a field of view. Additionally, it doesn’t offer substantially better image quality for the increased price.
When it comes to value, I think Sony has positioned the Sony 20mm f/1.8 very well in the market. It offers all the best features and top quality at a good price. Because of this balance, I think it’s excellent value and a great lens for astrophotography if you own an Alpha camera.
Sony 20mm f/1.8 Review | Conclusion
My summary of this lens is as follows: top quality, great features, good value.
If you want a lens to shoot in low light or capture the night sky, the Sony 20mm f/1.8 should be on your shopping list.
Prior to this lens being released, I bought the Tokina 20mm f/2 lens. Now that a Sony version has been released offering better quality and features, I will be swapping it out.
A fast wide-angle lens is somewhat of a speciality lens but I have found it to be extremely versatile. My main use is shooting astrophotography but I often find myself grabbing it to document my adventures and capture big landscape images.
If you want a great lens for your Sony a7 series camera, I strongly suggest you look at the Sony 20mm f/1.8.