Why is my glass material noisy and opaque instead of translucent? I have been following a youtube tutorial on creating a window glass material. In the tutorial the outcome is perfect but when I copy it the outcome is grainy glass which is opaque rather than translucent. I have tried turning the reflective and refractive caustics on and off both together and individually. But this at best only has minor effect.
It seems like Blender messed up. After messing around for a while to no avail I closed blender. When I went back to it and reloaded the scene the glass was transparent and the graininess for the most part had gone.