Okay, 3-D... what is needed?

jrazz wrote on 7/24/2005, 5:46 PM
Is this something that you would have to have special cameras for or is this a software thing? I am assuming it is software as polar express imax was 3-D and so was one of the nightmare on elm street movies. One was all animation- no cameras, and the other I don' t think that they would have used two sets of cameras to film it. I think it is software or film color separation, but what do I know... If I knew, I wouldn't have posted the question. Thanks for your time all of you who respond to questions on this user forum.

Comments

Chienworks wrote on 7/24/2005, 6:09 PM
True 3-D (stereo) visual reproduction requires two image sources. If it's a live shoot then two cameras (or a stereo camera, which amounts to two cameras in a single housing) must be used. If it's animated then two sets of frames with different angled viewpoints must be created.

While 3-D can be faked after the fact, it's usually a very poor imitation that tries various tricks to make you think you're seeing more than a flat image rather than being an actual 3-D image. One common trick i've seen a lot of people fall for is to have two copies of identical frames, offset very slightly horizontally, with one copy colored bluish and the other copy colored reddish. This ends up looking a lot like the old 3-D films that required the two-colored glasses. The problem is, even when viewed with the glasses this trick still results in a flat 2-D image. There are lots of people who don't understand the difference and will assume that they're partaking of a 3-D experience anyway.
jrazz wrote on 7/24/2005, 7:52 PM
Do you know the specs on the camera's (using two at two different angles). Do you know what the ideal spacing would be? I would assume that after this is done, I would lay one over top the other and blend them and render? I would also assume that I would need some kind of viewing filter to look through to see the effect. Do you know exactly what that would be or do I just need to contact my local movie theater for a pair of the newer glasses? Thanks for the answer.
jrazz wrote on 7/24/2005, 7:54 PM
For clarification, when I asked for specs, I was meaning the space between the cameras (how they should be set up). "lay one over top the other...", I am referring to the captured footage. Thanks.
Chienworks wrote on 7/24/2005, 8:24 PM
Ideally the cameras should be as far apart as normal human eye spacing. Moving them farther apart will enhance the effect.

If you're planning on a color 3D release you'll have to render two separate files, one from each camera. Both files will be played simultaneously using two projectors with polarizing filters over the lenses. The newer style 'color' 3D glasses are also polarizing filters. This allows each eye to see only one of the projections.

The old B&W style could be combined into a single file by coloring them opposite colors and using those color filters in the glasses.
jrazz wrote on 7/24/2005, 8:29 PM
Thanks for your answers...
If I am making this to put on a dvd for my niece so she can watch it on her tv, is there a way to combine it? It will be color and I don't intend on using it on a projector. I have seen some 3-D movies before on VHS and they may have been the old style, but is there some way to make them play on 1 source instead of two? Thanks again for your comments and help!
John_Cline wrote on 7/24/2005, 8:54 PM
If you want "true" 3D, then that requires specialized equipment, both for shooting and subsequent viewing. However, if you just want a 3D "effect" then there is the "Pulfrich Effect." It's a way of seeing a fairly convincing 3D effect on either a standard or HD TV. To create it and view it requires absolutely no additional hardware other than a pair of old sunglasses. Just take the pair of sunglasses and remove one of the lenses or, if you don't want to destroy a good pair of sunglasses, just hold a lens over one eye. The secret of the Pulfrich effect is merely that one eye is darkened. Although both eyes see the same image, the darkened eye transmits the image to the brain somewhat later because of a differential between the response times of the rods and cones in the eye. The brain calculates spatial depth information from this parallax that does not actually exist. It only works on video with a lot of horizontal movement, like an automobile race or certain parts of a football game. I shot a music video once that was all horizontal movement and we distributed cheap cardboard "Pulfrich" glasses, everyone was amazed and was convinced that I had done some sort of post-production trickery to achieve the effect. Of course, I hadn't, but the effect was quite convincing. The Rolling Stones did a music video once and made a really big promotional deal of it. The sitcom, "Third Rock from the Sun" did it too and had a huge promotional blitz behind that one episode as well. There is a lot of information about the "Pulfrich effect" on the net, Google it.

John
jrazz wrote on 7/24/2005, 9:57 PM
Thanks for the input John and Chienworks; I will google it and maybe do some test runs to see what effects I get from that method. Thanks again.
JJKizak wrote on 7/25/2005, 5:56 AM
As I recall, the camera lenses must be absolutely identical, without zooms and fixed lenses and not telephotos will give best performance. Zooms are almost impossible to match. Of course this is old film type information which primarily used standard fixed lenses for maximum effect. The articles I have read intimated it was a pain in the neck.

JJK
B_JM wrote on 7/25/2005, 10:18 AM
you will need to make a ANAGLYPH DVD..

See here on how to make them http://features.engadget.com/entry/1253716493759137/

or google search "ANAGLYPH" ..

You will need some glasses first ..

Now a issue you will find right away is that when you encode to mpeg2 the ANAGLYPH effect will not be the same as on your monitor or even from your NTSC preview monitor out of VEGAS .. when you encode to mpeg2 the encoder will change the color just enough .. so you will to do a couple of trials to get it right..

btw - i work with 3D for the film and entertainment industry..
JJKizak wrote on 7/25/2005, 11:48 AM
I forgot to mention that Canon has available an $8000.00 lens for 3 D.

JJK
jrazz wrote on 7/25/2005, 4:12 PM
Thanks for all the input, I will look up the anaglyph and follow the link. As for the 8000 dollar lens, that may be a few years off as this is my first 3-D attempt and I don't even know if it will be worth it.
I am using flash to create some animations and I am going to overlay them on some video to have them interact with people, etc on the actual film. Hope this anaglyph process works. I will do some trial attempts first to see how it turns out and then I will attempt it on the actual footage.
Thanks again for all the input.