SAY YES TO "PSEUDO"!

[P3D Dr. George A. Themelis <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Larry writes:

>In that same category we need a better term for *pseudo
>stereo* too. There is nothing *pseudo* about stereo whether it's viewed
>normally or inside out. It's like the relationship of male and female.
>Nature is full of both the inside and outside of shapes. It's not only not
>*fake* (the actual meaning of pseudo) but it's fully natural as well, though
>maybe unfamiliar in this context. That doesn't make it fake. 

"Pseudo" is another fine Greek word that means false, incorrect.  Perhaps
something in terms of "reverse" might have been a better choice, but I
have seen a couple of beginners mount their first rolls in reverse and
I can assure you that this is INCORRECT!!!!  Reverse-mounting a stereo
image is not "fully natural" when we are talking about an ordinary scene
that we are trying to visualize correctly.  It is "un-natural", it is
incorrect, and the reversed sense of depth is plain false.  

As a scientist I am aware of incorrect interpretations of topographical 
features when the 2d SEM micrograph is viewed upside-down (with the 
detector = light source, placed at the bottom instead of the top), or 
when a 3d pair is viewed in reverse.  Because of the lack of perspective 
or other two dimensional depth cues one can very easily do this _mistake_ 
if he/she is not careful.

As a photographer and "artist" (?) I have done my fair share of
experimentation and have been exposed to good "pseudos" but I do not
object to a term that says it as it is, i.e., the sense of depth is
"false", i.e. it is reversed compared to the one in the real scene.

Now, if a real scene never existed, as in a computer-generated wire
diagram with zero perspective, then both regular or normal and "pseudo"
or "reversed" views are correct and acceptable, but this is a very
special case.  That's the natural female-male relationship that Larry
is talking about.  But if you only introduce linear perspective to the
wire model of a cube then there is a conflict between stereopsis and
perspective if you want the cube to remain what it is supposed to be,
i.e. a cube.

My conclusion: "PSEUDO" IS HERE TO STAY!!! ;) ;) ;)

Thank you! -- George Themelis, stereo photographer and Greek Linguist


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End of PHOTO-3D Digest 1863
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