Turning on Global Illumination
One final thing before you render: You must tell the Photon
Director that you want to use all these values by turning on Global Illumination
in the Render Settings.
1. Click the Render Settings button in the Photon Director dialog
box.
2. Click the check box next to Global Illumination at the bottom of the
dialog box.
3. Click Ok in the Render Settings dialog box, then again in the Photon
Director dialog box
Note: I have found that on some computers, at this particular point in the tutorial,
this scene will not preview. (You can hit the preview button, but nothing
happen, except all the CPU cycles get eaten up by Mental Ray) So, in order to
see your results you may have to do a Render instead of a Preview. If
you end up having to render your scenes, turn on the verbose option (located
in Matter>Render>Options). This way you can monitor what Mental Ray is
doing in the status area at the bottom of the Softimage interface, as it renders.
Render (or preview). It should look like this.

Now some objects look way too bright and some look too dark.
First off, we have not added all the objects that should be
Receivers/Transmitters to the Photon Director.
Second, we have not adjusted the lights at all. (They are obviously too bright)
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