Question about 3D Glasses.

[Tom Wood]

Shademaster,

I have no experience in this area, but I did a recent websearch on the subject because I was looking into options for taking a monitor into a soundbooth while I recorded voiceovers. I want to control the computer while recording. I toyed with the idea of wearing a monitor while I emoted. Here's a website I bookmarked that has links to more:

http://www.nvidia.com/view.asp?IO=3d_stereo

HTH,

TW

[LucentDreams]

If theres one place to ask about stereoscopic systems its here ;)

First of all your lucky to have a few C4D users who are very passionate about stereographics. Phil McNally has a site discussing how to both photograph and render using c4D.

http://www.captain3d.com/stereo/index.html



As well you have someone who is currently threading 3D imax on an almost daily basis (ghost of the abyss) as an Imax projectionist. As well I get to go in tomorrow for training on the new lens system being used for the 35 mm action flick Spy kids 3D (yes thats right the third one will be 3D)

Basically all that is required is the two seperate images in the original source, and a method of limiting one image to its corresponding eye. Htere are many systems for this.

The most common ride and Imax 3D systems use Polarised (not polaroid) lenses, which basically limit light going through the glass to a certain polarity. So there are in fact two pojectors, one for the left eye image, one for the right eye image. A sheet of polarised glass (two panes thick) is placed infront of the lenses on each projector, one polarizing vertically, the other horizontally (so there is nothing special in the shooting or film printing process other then the fact there are two prints instead of one. Then the audience wheres glasses with polarised lenses corresponding to its projector, so one horizontal one vertical. The light going through the horizontal sheet, can only be sen by the glasses side that has a horizontal polarization.

The other older and now less popular method used alternating shutters on the glasses (very bulky and make a subtle but somewhat irritating humming noise) to actually block the image for the other eye, so right eye is blocked when left eye image is on screen. This one also uses two seperate projectors.

The third method is actually a col little cheat, there is a quicktime plugin that can even simulate this effect, which works much like the examples on phil's site. Using stereo images of cyan and red colour overtop of a mono coloured image. This is based on the original black and white, but is a little less effective as it tries to work with colour so the effect is dulled. This concept is mainly used with 3D Tv episodes (tool time, drew carey are two shows who have used this) They other thing they use to help it from deteriorating, is take advantage of Televisions Field system. Basically a television show is not truly 30 FPS in north america, but 60 (59.94 to be more exact) THey use the one coloured eye with the one fields and the other coloured eye on the other field, thus achieveing something similar to the shutter system.

The new one being used on Spykids 3D I don't know much about except the explanation our union projectionist said the other day, aparently they use a single camera with an extreme lens which then leads to two seperate normal lenses, allowing the two seperate images to be distorted onto seperate halves of the 35mm film. So the images are squashed horizontally to fit both eyes of a frame on a single frame of silm, the attatchment lens for the projector aparently will be the same setup but reverse the process, the overall image quality must not be as good, but will be interesting to see as it dramatically cuts down on filmstock prices.

As for seeing this on your monitor, there are special monitors you can purchase, and glasses for certain video cards as well.

[Shademaster]

Thanks a lot Tom and Kai! That was really usefull information :) .

I think my solution (for presentations) is to use 2 beamers with 2 polarised glasses. I think I can achieve the best effect from that method, even though it might be harder and more timeconsuming to achieve than with the quicktime plugin or photoshop.

My next quest will be to find good polarised glass for use on lenses and glasses :) . Hmm they probably won't notice if I borrowed some of those glasses from the cinema Kai is working...:p

[LucentDreams]

you'd have yto get them past the sensors at every exit
theya re very expensive

[Shademaster]

You got nothing to fear from me :p, I am right here in Holland where they (recently found that out) sell perfect polarised glass for use in windows. Just put those in front of the beamers and tadaa. I can get the polarised glasses from someone who works at a dutch 3d cinema. Those are very cheap, just a plastic frame and 2 plasticky glasses in them.
So I can finally begin making my own 3d moviiieee!!! Yeehah :beer: I'll keep you all updated :)

[Bmud]

polarized filters... why didn't i ever think of that??

my questions:
1. any suggestions for getting both films to sync up nice? Like if I was doing this at home or something, and I had two projectors..

2. use one computer or two?

3. polarized plastic sheets are what I'm familiar with which is what I think you're refering to. That should work. Is there a way to tell where "north" is on one of those sheets or are they typically labeled?

[Shademaster]

polarized filters... why didn't i ever think of that??

my questions:
1. any suggestions for getting both films to sync up nice? Like if I was doing this at home or something, and I had two projectors..

2. use one computer or two?

3. polarized plastic sheets are what I'm familiar with which is what I think you're refering to. That should work. Is there a way to tell where "north" is on one of those sheets or are they typically labeled?

1. If you have a videocard that has multimonitor support you can but both beamers/projectors on your videocard. Windows wil then create an extra wide desktop. If you want to sync it you have 2 options: Opening 2 mediaplayers in 2 different screens and trying to hit the play button at light speed (probably not the best option) or you could add both movies (left and right) next to each other in premiere so you'll have both movies in one screen. Then size it up in mediaplayer so the left movie is in the left beamer and the right movie in the right beamer (this worked for me). That should work.

2. You could use 2 but I don't know how to synchronize them both so they play both movies at exactly the same time.

3. polarized plastic sheets are exactly what you need :) , you can test "north" by shining with a lamp or spotlight projecting on a wall through one sheet while you hold another sheet in front of your eyes, if you don't see the light on the wall you have them both 'synched out' . This way you can let the left eye only see the image the left beamer is projecting and let the right eye only see the right image.

Hope that helped :)

[LucentDreams]

Originally posted by Shademaster
3. polarized plastic sheets are exactly what you need :) , you can test "north" by shining with a lamp or spotlight projecting on a wall through one sheet while you hold another sheet in front of your eyes, if you don't see the light on the wall you have them both 'synched out' . This way you can let the left eye only see the image the left beamer is projecting and let the right eye only see the right image.

Hope that helped :)

This brings up a good point, the polarized system isn't all that advanced, they are just plain film, its a polarized sheet of glass infront of the porjector that does the magic, if I was to place the sheets infont of the wrong projectors, then everyone would see faint shadows, they would have to flip their glasses over upside down to view the film (hmm should have tried that before I left the theatre:scream: )

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