hafner@ifi.unizh.ch (Michel Hafner) (05/13/91)
I'm working on a VGX and have written some code to show me an object against a background using the stereo-hardware. The results are less than perfect. There are annoying ghost-edges around the object. If you close one eye you still see this ghost-contour which seems to be part of the frame for the other eye. Is this a problem with the decay of the phosphor? If yes, can it be helped someway. If no, what else can cause these ghost-images and what can solve the problem? I have used different eye-separations, convergence-planes and colours ( for the object and the background ), but nothing really helps, unless you have two frames that are almost identical ( --> minimal stereo-effect ). Michel Hafner
gavin@krypton.asd.sgi.com (Gavin Bell) (05/14/91)
hafner@ifi.unizh.ch (Michel Hafner) writes: >I'm working on a VGX and have written some code to show me an object against >a background using the stereo-hardware. The results are less than perfect. >There are annoying ghost-edges around the object. Dark objects on a light background tend to have the least amount of ghosting (black on white is the best). Also, the LCD shutters in the glasses work better after warming up for a few minutes. Unfortunately, other than that, I think the only answer is a monitor with faster phosphors. Perhaps a monitor expert could recommend specific models, or perhaps there are some monitor-specific tips that could help (perhaps one of phosphors is faster decaying than the other two??). -- --gavin (gavin@sgi.com, (415)335-1024)
lmeyer@well.sf.ca.us (lhary meyer) (05/20/91)
Gavin's info is correct, the phosphors are the problem. I have been beating on the monitor manufacturers to provide a better stereo phosphor set, but to no avail as yet. I have searched the world and can't find a really proper phosphor for stereo, even in monochrome ( B&W). On almost all monitors the green is by far the worst (slowest) and then the red. Blue is usually fast, but who cares...your eyes have lousy accuity and sensitivity in the blue range anyway! ....Lhary Meyer // StereoGraphics
dave@imax.com (Dave Martindale) (06/08/91)
This isn't really a solution to the problem, but: Try to minimize the contrast between the objects of interest and the background. This might be as simple as using a grey background instead of a black one, or using foreground colours that aren't quite as bright. It's a fact of life that most 3D systems have crosstalk between the eyes. Film-based 3D using polarized glasses, red/green filter glasses, or LCD shutters all have this problem even though there is no phosphor decay time to contend with. Sometimes you just have to set up your scenes to minimize the problem as one of the costs of working in 3D. People using 3D systems with an independent optical channel for each eye (e.g. head-mounted displays) don't know how lucky they are.