Black reflection on glass I'm trying to render a glassy flac. The problem is, taht it makes black reflections on sides or corners. I don't know where these reflections come from, almost white world and in the example the flac is in white cube and still there is black left side.

What can I do to get rid of these black spots?
In the render properties for cycle find the Light Paths and increase the Transmission value till the dark spots go away.