| Calvin wrote: Quote:moviePig wrote: No... the red filter blocks that image made of blue light (as you've just realized), so that the eye behind the red filter can't see the blue image at all. (When your red-filtered eye looks at blue characters on your calendar, they turn black. The same thing happens to a projected blue image, i.e., it turns black... but, because you're in a darkened room, turning black is equivalent to vanishing. It would be logically (though not necessarily psychologically) easy to capitulate at this point and make an analogy, which you seem to be making, between the blue/red and the right-angle/ polorizing processes. I think we both see how that analogy would be made so I wont go through the tedium of making it. There's a similarity to polarizing, in the sense that like passes like (and blocks unlike)... but the physics is way different, afaics. So, no, I'm not flirting with an analogy. Quote:But let's talk about screens and darkened rooms for a bit. A movie screen is designed to be both highly reflective of light, and minimally intrusive from the unlit parts of it. Thus it can show a moon and stars in a night sky quite effectively if the room is dark. Thinking of the screen as basically dark, I can see how that supports your view. Project red and blue 3D images of fireworks on it and your explanation would appear to be proven. But if we're looking at a red/blue 3D picture of a bright desert at noon, where the brightness of the screen is the dominant condition, then I'm not sure how your explanation could apply to, say, an originally solid black car and an originally solid white car, before they were photographed by b/w dual cameras and converted to red and blue noon desert scenes of cars on a highway. The black car gets projected as black in *both* images. The white car gets projected as red (at maximum red-luminance, i.e., equating to white) in the red image... and likewise as blue in the blue image. (Meanwhile, note that the only reason you can even see the black car in *either* image is because of the surrounding, presumably gray, desert. I.e., the black car is, in a sense, a car-shaped absence of both red and blue light.) -- /---------------------------\ | YOUR taste at work... | | | | http://www.moviepig.com | \---------------------------/ |