Three Dimensional CT Reconstruction.

John Wattie and Tim Sheehan


Viewing Methods


   Cross Eyes Version 

   Parallel Eyes Version


   Grey anaglyph

   Coloured anaglyph

Aortic aneurysm

X Stereo

  • You need to [go cross eyed] (X stereo) for the big 3D stereo pairs.
  • 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.

U Stereo

  • 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 pixels enlarge.
  • 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.

Colour anaglyphs

Because a few people cannot do ocular gymnastics, also included are

 [red/ blue-green anaglyphs.]

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 contents page]

[Return to 3D picture gallery]

[Go to stereoscopic x-rays of a sea shell]