Problem with sun ligths

I’ve a very simple scene:

  • Layer 1: Sun1 + Cylinder casting a soft shadow on a wall
  • Layer 2: Sun2 + group of cubes

If I render only Layer 1 I obtain a soft shadow -> OK

If I render Layer 1 + Layer 2, the shadow becomes sharp, and I don’t want it. I want the shadow to remain smooth. The two Sun are identical (both to cast smooth shadows), and moreover I have set ‘This layer only’ for the Sun in Layer 2 (Sun2), but this doesn’t fix the problem. The Sun in layer 2 keeps on modifying the shadow of the cylinder in Layer 1.

Here the .blend

050 – test non buono–2-.blend (1.41 MB)