Using one camera - Making 3D in post?
 

Hi everyone,

Is it possible to replicate the use of two side-by-side cameras with one camera and an NLE to get the 3D effect?

If I have one shot to work with, layer that shot, move them apart horizontally to the right distance, and make the top layer more opaque, haven't I just made it as if two cameras got the same footage?

Thanks.

it should be possible, with some cropping. I am using the Newtek VT5 with a pluggin that will do it in live production, or in the editor in post.

That will just be seen as a 2D image, each eye seeing the same thing. The 3D effect really requires a difference between the images to be meaningful. IMO.

Sure, as long as the camera uses a stereoscopic lens.

Thanks guys.

But if the image is seperated and each image is changed in color - blue and red - doesn't that give the "old" 3D effect.

I thought I read somewhere that it was possible. i can't find the post again - might not have even been this site.

The only effect that would give you is bring the entire 2D image closer to the viewer or pushing it away from him.

There was a cool trick someone posted on YouTube. He took a video sidewise from a tram, as it was moving slowly. He then picked the right stream couple of frames behind the left. He got a pretty cool stereo effect, as long as he took just a stationary landscape, not moving vehicles, so he didn't need very good synchronization of the two streams. Of course this has a lot of limitations, but I thought it was clever way to get "real stereo" with just one camera and lens.

Maybe by using greenscreen ....
 

I've been thinking of trying a psuedo-stereoscopic effect by shooting several people (one at a time) in front of a green (or blue) screen. Then making two separate chromakey composite shots, almost identical, but with slightly different left-right offsets, to make some people appear closer than others. And of course, compositing in a distant background. You would only need one camcorder to do this. With a 3D animation package, you could generate two different background animations, one with the camera position horizontally shifted from the other.

No, I haven't done this... yet. But I suspect a similar trick was used to create a short stereoscopic sequence in the recent Harry Potter movie (while the group is flying at night).

Ken

Glad to see this mentioned. I did a similar concept using the slow motion high speed shutter capability of my Sony HDR-CX7 camcorder. At 150 fps you would get about a 3" separation between frames at 25 mph. Unfortunately the car was moving at 70mph while I shot my video out the window and it only shoots for about 5 seconds producing a 15 second clip at normal speed. At the high frame rate it works pretty well, there is very little change in exposure or focus/zoom as well as hand held movement between frames so slipping a frame for left eye/right eye video matched up pretty well. I didn't have control over the subject matter, obviously not a practical technique for serious 3D production but it is good for producing a stereo image with one camera and nothing else but your video editor for practice, IMO. I believe the Canon DSLR has a high frame rate possibility but at a much reduced image size but that would allow longer video sequences I think.

Anyone comfortable messing around with Avisynth can play with the one-camera approach, as long as your video contains some amount of lateral movement; there's a plugin available that accomplishes something like this called fauxD. The file's attached to the first post, and you don't have to be registered to download it.

The author stresses that he is aware the results aren't a substitute for real 3D, and that the plugin is only a fun toy to play around with. Further, he makes a point of strongly suggesting you only view clips with this tool for short periods, lest you risk severe headaches.

If you still want to try it, it's not too difficult to get set up. Once you have Avisynth installed, you'll need to download MVTools 2, a motion estimation/compensation plugin that fauxD makes use of. Extract mvtools2.dll to your AviSynth 2.5\plugins directory (which will be C:\Program Files\AviSynth 2.5\plugins if you opt for the standard installation). Then, from fauxD_v012.zip, extract both fauxD.avsi and fauxD.dll to the same place.

One final adjustment is necessary to get this working, and it's in the script itself. Open up fauxD.avsi and look toward the top for the two LoadPlugin lines. You'll need to replace these:

LoadPlugin("D:\somepath\MVTools.dll")
LoadPlugin("D:\somepath\fauxD.dll")

With these:

LoadPlugin("mvtools2.dll")
LoadPlugin("fauxD.dll")

No need to type out the path, since the DLLs are in the same directory as the script you're editing.

Then just make an .avs and add the line

fauxDit(AVISource("C:\video.avi"), 0, 40, true)

changing the video path and filename to suit your clip. The number after the AVISource is the 3D mode used. 0 is the default, and produces Red-Cyan anaglyph video. 1 is Over-Under, 2 is Side-by-Side and 3 is for use with interlaced shutter glasses.

Open the script in VirtualDub and see what you think! More detailed instructions can be found in the included documentation, but that should get you up and running. Honestly, I have no 3D glasses at my disposal to test the plugin, so although the results might be worth the effort, I can't guarantee it. Please don't get your hopes up.

That Doom9 thread also mentions the 3Dfier DirectShow filter. Apparently you can get a free demo that runs for about ten minutes, a full personal-use license for $25, and a commercial license by contacting the developers. Again, I can't begin to vouch for this, as I have no way to test the results, but if anyone here does you may want to try out that demo.

In your case you would have to mask out foreground and background layers and "move them apart horizontally" separately. The foreground should not be moved apart at all, and the background should be moved apart the furthest. -the more layers that you mask out and adjust separately, the better. That's essentially how side by side cameras record (as opposed to not the real deal beamsplitters), but when you do this on the computer the layers will appear flat like a cardboard diorama.
There is new technology that is being used for old movies like Star Wars though...

Mike, you might want to check out Ken Stone's Final Cut Pro Web site by Eric Cosh.
They are experimenting with 3D.

This should be possible; i will give the 'kijkdoos'-effect (I believe the English word for kijkdoos is showbox).
Your characters will remain flat, but you can position them is the 'space'.
The term pseudo-stereoscopic is well chosen.

Anyway, did you start with this project yet?

But people are three dimensional, too. If you do what you are proposing, you will have two-dimensional people placed in front of a three-dimensional background. Your actors will look like animated cardboard cutouts.

I was thinking that shooting from a distance (maybe 12 feet) gives a flat effect anyhow, so my "cheating" might not be noticable.

And no, I haven't started the project. After reading so many posts about the expense of a quality stereoscopic display, I've deciding to wait for prices to lower. But I'll be keeping an eye on this forum.

Ken