CompuServe Messages

Jason: About "experimenting" with stereo-pairs: I used to do quiet a lot of normal stereo camera work…..some hints: – If the camera lenses are parallel: the objects appear in front of your screen! You have to converge the cameras at the 'far point': all object appear then behind the screen (like looking into a theater setting). – The scene boundaries represent in stereo this kind of 'virtual window'. That means an object which doesn't fit in the scene and is placed IN FRONT of the virtual window is cut at the picture edge, which gives you a disturbing 'visual unlogic' situation. – In 3DS you can easily find the place where the 'virtual window' will be: if you switch on the camera cones, the stereo-window is in the plane where the two cones intersect (in top view). – BTW: the distance of the two cameras (the two eyes) is most important. As a rule: imagine the scale of a human figure in the setting and the relative distance of his eyes (ca. 2.5 inches). If you set the cameras more appart, you'll get what's called 'giantism' (the relativ human figure would be a giant; the 3D scene appears like a small model setting). The other way round (narrow camera distance) you'll get a so called 'lilliputism' setting. – For a very general rule: Try setting the cameras about 1/30 of the distance to the 'near point' (=the nearest object to appear in the scene). This will give you a good, not 'overdone' angle. – About the 'virtual window': you can have objects leaping out of the window (=being nearer to the cameras than the 'window plane'), but as mentioned these objects shouldn't intersect the picture edge. (…an effect often used in the stereo movies of the 50's….). Just two days ago I tried some 3DS stereo stills, changed the colors to the well known red/green afterwards and combined them to a single picture to view with the simple red/green glases (worked quiet well….a good green/blue color is always difficult to find). Hope this helps a bit…..(good stereo is not that easy and has certain rules….) I could name you some good books about the theme (dealing with general rules and photographie), let me know if you need some more information. …………………………………………..Alexander.