I bought all three of the Sigma-lenses (19, 30 and 60mm DN Art) but it's only the 60mm that works and is recognized by the Go-app. The 19 and 30mm locks when trying to take a picture because the aperture-controll doesn't work. The app also say "Unknown lens" so I'm very annoyed by this. It doesn't make any sence because the 60mm works just fine, and the others are excactly the same. This has to be a fw-issue, and I think it should be addressed because the lenses balance so well. Hope someone has a fix for this so I can start taking pictures with them. Here you can se a picture I took with the 60mm yesterday. The closest house is about 6-700 meters away, the town center behind the church is about 3,5 km. away.