I think that’s simply a reflection that is blending some ray traced reflections and screen spaced reflections. That’s pretty normal
Try removing some of the foliage and see if that helps at all
Unfortunately no … I removed all the trees in the area as a test. The surfaces in the room are now generally darker - but the reflection is even more full of black streaks, the tap is only half visible. I can heal the reflection retrospectively with image processing, but surely there has to be a setting that works?
Hi @doro_thee
Please have a look at our post here regarding reflections, as real-time rendering brings some limitations.
Additionally, if that does not help, can you perhaps mark in the image where the issue is or say what isn’t reflecting correctly, as it is somewhat hard to see from the image alone (also what entirely is the mirror).
Thank you very much, the info helps me to stop experimenting with the settings …
I removed the people, then only the tap in the mirror reflection is interrupted. I can live with that.
And I hope not to have to design any more bathrooms in the near future 
