I have your book and have been experimenting, but I realise I am not clear on the difference between GLOW and SELF GLOW and when one would use one over the other.
For 'quick and dirty' neon light which would I use: Glow or Self Glow, as opposed to creating a light source behind a coloured translucent material.s
I would also like to put a glow on the image on the cinema screen - what do I use for that. I deduce I could perhaps make the film image a transparency and put a light source behind it, but it seems a lot of work if one of the glow functions would suffice? Same applies for TV screens, computer monitors and pads.
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"Glow" makes a material a source of illumination, the same as if it was a light.
For things which are indeed a light source, then Glow is more Photorealistically correct.
(But see the additional comments below)
"Self Glow" make a material brighter as if a light were shining on it, but does not ever cause the material to act like a light itself.
Neon Lights
For Neon Lights which illuminate the surface behind them, or cause shadows to be cast, Glow is better.
However, in most cases Self Glow will work fine.
Televisions and Theatre Screens
Again a television in a dark room or a Theater Screen may cast light and cause shadows, but in most cases Self Glow will work just fine.
See: http://www.renderplus.com/wp2/wk/Glow.htm for more details