First of all: create 2 Boxes (Poly or Nurbs doesn't matter) !

The 1st Box is a liitle bit larger than the 2nd.

create a point-light (a Maya default one) !

Set: Turn on "Emit Photons" under Caustic and Global Illumination !
Exponent : 1
Physical : off

Create a sphere (Poly or Nurbs doesn't matter) and place it right below the pointlight !

now create a small plane and place it beneath your pointlight so that the normals show toward
the sphere and the pointlight!

name this object 'PhotonCollector' !

Place a camera inside the inner box - so that you can see the sphere !

Modeling is done ! -> lets continue with the shader assignment !