Thanks for the replies. I want to make the scene as photorealistic as possible and most of the tutorials I have seen have pushed me towards Mental Ray and mia materials for this. Perhaps I don’t need to rely so heavily on making geometry emit light but it’s frustrating that I can’t get this to work. I’ve actually come across a number of strange issues of things just not working properly and suspect it’s because I’ve been working on this scene for a number of months and it’s become an extremely complex one with numerous objects and textures and some errors have accumulated over time.

I am using lights with IES profiles for the streetlights so there will be some other light in the scene. Plus there is some residual light from a physical sun and sky with the light angled so that the sun is just below the horizon. I’m doing the glow in the scene, using a lambert because I understand mia materials don’t offer this effect. Is there any particular reason why you say I should do this in compositing?

I’m not sure, Jay, why you consider my approach so convoluted. I’m doing pretty much the same as you’re suggesting, only using mia materials.

Gen, if I’ve understood you correctly, you’re suggesting I reflect a light with the appropriate colour off the mia material and light surface in order to make it illuminate the surrounding area more effectively. Is this correct?