P3D eye focusing by chromatic aberration

[Peter Abrahams <telscope@xxxxxxxxxx>]

>From an eye doctor I know:  The general notion of chromatic
aberration as a cue to accommodation is fairly widely accepted and is in
textbooks.  The most current and compelling work (including the effects of
doublets that reverse chromatic aberration) has been done by Phil Kruger at
SUNY Schnurmacher Vision Research Institute in Manhattan.  Mostly
published in the journal Optometry and Vision Science.

>From: roberts@xxxxxxxxxxxxxxxxx (John W Roberts)
>....- it has been reported on P3D that humans apparently
>use chromatic aberration in the eye (when the colors in the scene make it
>available) as a feedback mechanism to achieve focus.

I believe that any color except black would be refracted by a simple lens
into colors, no particular color would be needed.  Some minimum intensity,
and some fairly sharp edged objects, might be needed.

 Does the aberration
>profile (degree as a function of distance from optimum focus) of a 3D camera
>lens (or camera-viewer / camera-projector combination) match closely to that
>of the human eye?

The chromatic aberration of a lens would be registered on film, and placed
in the viewer at a set distance from the eye.  It might confuse the eye,
but the image on the film should in general be treated by the focusing
mechanism of the eye as any object at that distance would be (the distance
the lens makes it appear to be.)   It would be a wild coincidence if the
chromatic aberration of a camera + viewer  matched the eye.

> In any event, the aberration degree and direction (if any)
>are "frozen" in a still photograph.
>
>Another possible issue - depth of focus as a function of brightness of
>illumination of the scene [Note]. (Though if you're looking at the depth
>that was in focus in the original photograph, it might match up.)
>John R

There is something of great interest here, but I lost it by taking this out
of context.   Can we have an elaboration?
_______________________________________
Peter Abrahams   telscope@xxxxxxxxxx
the history of the telescope, the microscope,
    and the prism binocular


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