Conclusion

The ultra-wide-angle Lumix S 18mm F1.8 is the fifth f/1.8 prime lens that Panasonic have released, joining its 24mm, 35mm, 50mm and 85mm siblings, and as with all of those lenses it's another excellent addition to the range.

There's lots to like in terms of the Panasonic Lumix S 18mm F1.8's image quality, and very little to complain about.

This lens is sharp almost from the get-go, excellent in the centre of the frame when shooting wide open at f/1.8, and simply outstanding between f/2.8 and f/11. The edges aren't quite as sharp as the centre though, producing the best results when stopped down between f/5.6 and f/11.

It's capable of producing some very nice bokeh effects for what is after all an ultra-wide-angle lens thanks to the 9-blade circular blades and f/1.8 maximum aperture.

There is some obvious vignetting wide-open at f/1.8, but this can easily be corrected in post-processing, or you can stop down to f/4 to help avoid it altogether.

Chromatic aberrations are very well controlled and it even produces some nice sun-star effects at f/16.

Perhaps most importantly for such a wide-angle lens, there is very little barrel distortion in either the JPEG or RAW images, testament to the high optical quality.

The build quality is very good, with the built-in weather-proofing offering some peace of mind in more inclement conditions.

Auto-focusing proved to be fairly quick and reliable on the Panasonic Lumix S1R camera body that we tested the lens with thanks to the 240fps linear motor.

In addition the focus mechanism is barely audible, making the lens very well-suited to video use.

There's no manual focus over-ride available at any time, though, and the lens lacks its own optical image stabilisation system, instead relying on the camera body (if it has one).

With a full retail price of £799.99 / €899.99 / $999.99, the Panasonic Lumix S 18mm F1.8 offers a lot in terms of its value for money.

It makes for a well-balanced partner when paired with the larger Lumix S1R camera body that we reviewed it with.

Overall, the Panasonic Lumix S 18mm F1.8 is a fast, high quality yet still affordable ultra-wide-angle prime lens that all Panasonic S full-frame camera users should strongly consider adding to their camera bags.

Ratings (out of 5)
Design	4.5
Features	4.5
Ease-of-use	4
Image quality	4
Value for money	4.5