As has been discuss previously, the amount of stereo effect is defined, in part, by the separation of the camera lenses, which defines the relative parallax differential between the left and right eye images, and can cause problems when attempting to bring the two images into focus.

There is another effect of using a large inter ocular distance - that of miniaturisation.

The following image has been shot with a relatively normal inter ocular distance of approx. 1.5 inches, and looks fairly natural to look at. (The image is black and white as the original colour image was predominately red; a colour that can't be seen via anaglyph red/cyan glasses.)

While this following image has an inter ocular distance of some 8 inches.

With the exaggerated stereo effect comes both a lengthening of the apparent distances between objects, as well as the length of the objects themselves, obvious by comparing the above two images (look especially at the distance between the character's shoulder and head), but more importantly this second image gives the impression that the objects are all miniature models, not life sized...

This is due to the amount of 'stereo' being more equivalent to that generated by a small object very close to your eyes, rather than a larger object further away from you. Therefore your brain is telling you that with such a large amount of 'stereo' the objects must be small and close to your eyes...

Conversely, using small inter ocular distances, below that of the average human eye's 2.5 inches, generates a feeling that the objects being viewed are larger than they are in reality, due to the reduced stereo effect!

Next Page - Convergence and Focus

As always, test before committing to a particular style of stereoscopic 3-D shooting.

Or better still, contact steve@lightillusion.com for more info.