Three Dimensional CT Reconstruction.
John Wattie and Tim Sheehan
- You need to [go
cross eyed] (X stereo) for the big 3D
- Your eyes must be on the same
horizontal plane before attempting this feat - don't tilt your head.
To go cross-eyed, look at
your finger placed about half way to the computer screen, fuse the
images, then let your eyes refocus in their own time.
Otherwise look through a [4cm square in a sheet of cardboard,] aligned so each eye can only see the
correct picture of the stereo pair.
Or use a $US20 Vivitar card viewer which is made for Vivitar camera prints in cross-eye format. It works on computers too.
- Some prefer to use
[parallel viewing stereo] (U stereo)
- Smaller pictures are used for that,
because most people's eyes will not diverge past parallel.
- U stereo means less resolution on a
computer screen, because less pixels make up the picture.
- U format does allow a standard 3D
viewer to work - but viewer magnification is not too edifying when the
- It may help to put your
face up to the computer screen, relax the eyes, then slowly pull back.
- Keep looking
through the screen into the distance.
- If the separation seems too great for your eyes,
move further back from
the screen and they
will not have to diverge so much.
few people cannot do ocular gymnastics, also included are
Liquid crystal glasses
The image format used for
the X stereo version is suitable for liquid crystal glasses using the [Depth Charge program]. With a fast video card, this is a good way to see computer stereo
and is supplied with some radiology work stations, e.g. Siemens MRI.
[Return to stereo
[Return to 3D
stereoscopic x-rays of a sea shell]