The Olympus M.Zuiko Digital 17mm f1.8 is a prime lens designed for general-purpose use. With an equivalent focal length of 34mm, it delivers a field of view that’s almost identical to the classic 35mm lenses adored by street photographers. As such it’s comfortably wider than a 50mm equivalent without suffering from the distortion of 28mm equivalent and wider options.
This makes it ideal as a walkaround lens, while the light weight and small size means you’ll hardly notice it’s fitted. The bright aperture is useful in low light and can also deliver shallow depth of field effects especially if the subject is close to the minimum focusing distance; if you’re careful with distance and placement on the frame it can even take a reasonable portrait.
Downsides? The lens hood is optional, there’s no weatherproofing and the price is quite high, but the quality is great and it could end up being your most used lens, especially if you don’t already own the 20mm. If you’re after something higher-end and slightly wider, consider the Lumix / Leica 15mm f1.7, also in this guide. I’ll be adding samples and results soon.