global illumination not working
 

i am following this interior lighting in mental ray tutorial
http://www.treddi.com/forum/index.php?showtopic=8436
it's quite good so far
well now I’m at the point where I have to turn on global illumination so I did, but there is no difference at all between the render with out global illumination and the render with it. its just not working, what’s going on?

I have attached the image with global illumination enabled

whats going on?

I believe section 1.2.1 Sunlight of the tutorial covers this.

ok you have to emit photons to have global illimination so whatever your light souce is you have to select it and go to the attribute editor and under the Mental Ray tab check on Emit Photons, you may have to tweek the amount of photons to get the desired result so this can envolve a bit of time and many check renders.
If you do not have any Lights you can create one and have it emit photons only by turning off it's intensity.

oh sorry i thought i said i had already done that, no matter how high i set the photons emited nothing was changing.
any more ideas?