P3D Re: SI anaglyph

[Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

Ray Hannisian wrote:
>> In print, the anaglyph presentation lost enough detail to create
>> a strong "card-board cut-out" effect. 

Then Tony Alderson replied:
>I don't think the cardboarding effect has anything to do with any "loss
>of detail" in anaglyphs, but is due to a mismatch of the angles of view
>in photography and viewing. (But I don't think there is any inherent
>loss of detail in anaglyphs, and I don't think loss of detail leads to
>cardboarding. Staircasing or stereo aliasing, perhaps, as the relative
>pixels grow, but that's not the same thing.)

This is confusing. Your saying "staircasing" is not the same thing, as
cardboarding? Can you elaborate? 

I agree in the example with Heidi (and Bruce that just posted
a few minutes ago), that there is a stretch/squash effect, but I don't
think the perspective is a better match. In what sense do you mean
better match? If you stand back a few feet, it's sure not ortho! Look
at her arm, it looks like it's 3 feet long!

Furthermore, there is no roundness to her arm (if that is what your
referring to). Granted there more depth, but within her arm there
is no depth. It looks like a flat piece of cardboard coming at
you. Same for most of the faces (other than the nose area) and other
parts of the body.

I have to agree with Ray and say, the cardboarding I believe, is due
to loss of detail. The stretch/squash IMO is another completely
different factor. Why do you think B&W anaglyphs work much better?
It's not only because of the color rivalry, but also I believe
because of the loss of detail in the red channel! Quite a few of
the images have NO red channel detail, and this is the problem. 

For example, look at the Universal Studios ad. This ad has very
close up shot of a model's face and no stretch is required to see
the depth in her face. It's the best image in the magazine! Why?
It's not in color! :-)

Also you notice pronounced cardboarding with cheap cameras. Take
a cheap camera and a good camera with the same focal lengths,
settings, etc., and see if you don't get cardboarding with one of
them. I know, I have a lot of experience with cheap cameras! 

>Personally, I think the SI issue was overall pretty good, and
>won't hurt 3D at all. You notice, BTW, the publishers had a
>lot less confidence in anaglyph TV, which seemed reluctantly
>squeezed into the show for gag value only. Not even a gimmick,
>there!

I agree. I should mention,  I don't want the people involved, to
think I'm criticizing the production of this 3-D issue. I think
they (Ron included of course!) did a fabulous job. I loved it!
Sure, it wasn't perfect (I would have preferred it be all B&W
anaglyphs, and some other minor points, but hey, you can't have
everything, also I realize the constraints of having to please
many masters), but considering the hurdles, you've ALL succeeded!


>Fair enough. I'm amazed we've had controversy with invective
>for several days running! I'm gonna hafta go back to watching
>wrestling.

There was? Hey, how long have you been on P3D! ;-)

>I'll have more to say (separately) about anaglyphs and
>cardboarding.

Great, I hope I added some more fuel to the fire. :-)

>It's a rainy weekend in LA, and I've got a cold. Forgive me for sharing
>my misery.

No problem, get well soon. I was sick in January and didn't even
go near a computer! Also, just to set the record straight (in case
this message is taken differently), I do greatly respect and enjoy,
Tony Alderson's In Depth 3-D work and knowledge!

Gabriel