I'm trying to create projection of objects in my scene onto one specific object (in my case a sphere). In theory it is simple, by giving the object a reflective surface but here is my problem, the sphere has to be semi-transparent. Meaning it should be reflective and showing the other objects in the scene clearly but at the same time then parts of the sphere not showing any other object should be semi-transparent. I'm trying to get this working with cycles (cycles is a must) but no luck so far. I'm open for any ideas.
Update: I created a small test case containing my sphere and a cube with a marked corner. The reflection of the cube is on both sides of the sphere but I want it to be only on the side pointing towards the corresponding object. Additionally, the Mix Shader of the Glass and the Transparent BSDF turns the reflection grainy (for lack of words).
Update 2: I found a way to remove the unwanted reflection but this results in the reflection that I want to only be visible from the direction of the reflected object. I can not see the reflection through the sphere, which is the reason I want the sphere to be semi-transparent.