Re: John!!!

[P3D William Carter <wc@xxxxxxxxxxxxxxxxxxx>]

Paul Kline observes:

>The present catch is that W. Carter has his own experiments showing
>a greater-than-expected ability to encode depth, and a theoretic
>model that is consistent with those experiments.

He describes the objective of my model:

>The Rayleigh criterion applies to two points at the same distance
>from the lens.  What is the criterion for points at two different
>distances?

And, compares predictions based on my model vs. centroid-as-baseline.

>Bill's model predicts that leaving the apertures wide open
>enables us to distinguish A and B at even smaller separation... (etc.)

John B concludes:
>... I would say that when you claim a radical way of looking at something 
>is the true way, the burden of proof falls heavily on you. 

I think we've arrived at the natural conclusion of this thread: 
Does the SL3-D system behave as a dual lens system or not? If not, why 
not?

A few years back I shot some SL3-D pairs. They were close-ups (I used 
the only lens, a close-up lens, that I had modified at the time). It should be 
noted that these photos where overexposed and a little grainy.
 
In one stereo pair, I noticed some overlapping fibers.These fibers formed a 
nexus, and were only separable by their stereo depth. I measured their 
diameters at the subject, and found them to be 3 to 4 times thinner than 
the centroid-as-baseline model would resolve.

I then set up and shot several targets in an effort to define the stereo 
resolution for this system. An angled rule to "ball park" a resolution. Then 
a series of grit sizes to hone in on it. These were carefully lit to eliminate 
shading. 
The results showed a depth resolution of about 10 times greater than could 
be expected from the old model. Why?

The new model I'm proposing seemed an obvious answer to this dilemma.
As Paul Kline notes, "Gee Bill, this is really simple when you think about 
it." 

As a foot note, a Neuroscientist, William Martens, PhD., was charged by 
an interested third party to research the depth resolution of this system. 
He never finished his investigation (as far as I know). However his 
preliminary findings led him to announce that they "Seemed to 
substantiate (my) findings".

The difference between these two models is not subtle. They lead to vastly 
different conclusions and expectations. 
I realize more testing, under more scientific controls, needs to be done. 
The model I proffer may not be correct. But, it does fit these early tests, it 
is a simple model, and it's intuitively obvious. The predictions of a 
centroids-as-baseline model are grossly in error. It is nowhere near being 
correct.

-- 
                     mailto:wc@xxxxxxxxxxxx
    37deg 39.09'N x 122deg 29.56'W x 90'MLLW







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