Zero-D means zero distortion and Laowa means business when it comes to the 9mm f/2.8. Compatible with all sorts of systems, including the Micro Four Thirds, Fuji X, Sony E, Canon EF-M, and the DJI DL, this little lens is both lightweight and portable.
As with previous Laowa products, there's no negativity with regards to the build quality of the 9mm f/2.8 lens. Solid, metal built, compact, it feels good in the hand and balances well with the lightweight OM-D bodies that we tried it on (E-M5 MkIII, Pen-F). The Unique Selling Point of this lens though, is the Zero-Distortion feature.
If your purpose is to photography interiors or landscapes with lots of straight lines in your frame, this is the perfect lens with next to no distortion detected (as far as we can see, anyway). This means there's no loss of pixel or correcting the image in post which rocks. It's always best to create the image that you want in-camera and here, the lens does just that for you with regards to distortion.
In terms of image quality, we have no complaints. It's very sharp, corner to corner, especially if you stop down to f/5.6 to f/8. There is a little bit more flare apparent than when using the Laowa 7.5mm f/2, but a part of that is because of the petal shape of the lens hood. Perhaps a different shape would suit the 9mm a little better.
If you're going travelling and you don't mind manual lenses, the Laowa 9mm f/2.8 is a great landscape option - remember that at 9mm focal length, it is the equivalent to 18mm on a full frame camera and that's plenty wide for the sights you'll see on your travels.
Reminder that this is a manual focus lens, which gives you great control but doesn't allow for your camera body to perform auto-focus tracking tricks. Also, beware that if you're relying on your in-camera image stabilisation for some shots, you need to adjust focal length on the IBIS setting accordingly.