P3D Re: Curious Deep Math Tale

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

OK, here is another way of putting this:

Both the depth of field equation and the stereoscopic deviation 
equation are related to the inverse of distance.  If your lens
has DOF markings, you can use these markings to obtain stereo
depth range instead of depth of field.  

In that sense, it is just a trick, using one scale built for
one purpose, to calculate something else.

But, you could go beyond the trick and start thinking of physical
relationships between the variables involved.  Two objects at
different depth levels will give rise to deviation in stereoscopic
photography and also bluriness in single photography.  Even the
single photograph contains depth information.

Lenny Lipton somewhere defines a "hyperconvergence distance",
which is the equivalent of the "hyperfocal distance".  I have
forgotten the details on this... but clearly there is more in
this similarity than just a calculating trick.

George Themelis


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