P3D On eye separation and viewing

["Hans A.J. Middendorp" <ajhans@xxxxxxxxxxxxxx>]

Bruce Springsteen wrote in P3D 3744:
...
>So infinity will be at zero convergence no matter what part of the
>lens you look through, no matter how far apart your eyes are, as >long as
the lenses are sufficiently large for you to see a whole >image in each.
>
>The interocular adjustments on viewers, not for interpupillary >matching
purposes at all, are equivalent to the horizontal >adjustment on a
projector - they move this "infinity center" off >your center of vision,
either making you diverge infinity and >creating frustum deformation away
from you, or making you converge >infinity and creating frustum deformation
towards you. 
...

I've read this before, that interocular is not important, but :-) :then why
can I always tell when my wife has been using the viewer? It is
_defenitely_ inconvenient viewing [or 'frustrating', pun intended :-)] when
the interocular is adjusted to smaller faces.

Having not really understood the frustrum discussion a couple of months ago
on this list, I usually realise that something is possibly wrong with the
relative spacing of the chips if I suddenly need to adjust the interocular
from its usual position. The question is, has this anything to do with
frustrums or is this something else again?

Thanks for your patience :-)

Hans
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