P3D Re: Judging of Stereo Cards

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

Bill Walton wrote:

>In regards to viewing devices- That is a tough call as there are so many
>variables.  In the 1st SSA we used Keystone N50 Training Stereoscopes.  I
>say used, but I should say the judges had them available.  The Three
>judges were Stan White,Paul  Wing and Larry Moor  and all of them judged
>by free viewing the stereo cards.  In the 2d SSA we used Red Wing
>Viewers, which have hoods big enough to be able to be used by those who
>wear glasses.  In the upcoming 3rd SSA, closing date 11 July, we plan on
>using Keystone 46b Visual Survey Telebinocular stereoscopes.  George
>Themelis has reported on the quality instrument several times and I would
>think that most of the P3D group know what it is.  But to cut to the
>chase, use whatever viewing device you have as long as all the images are
>viewed using the same type viewing device. 

As Alan Lewis pointed out earlier, the viewing device used will certainly
affect the results.  Going from an achromatic stereoscope to freevieing
is a big step.  In regards to the sharpness, it is certainly possible
that a "soft" print is not seen as soft in freeviewing.  Other qualities
take over (i.e., stereo effect).  "Stretch" is also present to a great
extent during freeviewing.

>To put in the regulations what sort of viewer your judges will use is
>sort of wasting space in the regulations, I THINK.  Who cares, as long as
>all the images are viewed by the same type device.  A good parallel would
>be to put in a stereo slide exhibition what kind of polarized glasses the
>judges will wear, so you can decide what type  of slide to enter.   The
>main thing about this whole operation is to have FUN and once you start
>trying to overegulate it then the fun disappears..

With regards to the *type* of polarizing glasses, the comparison is not
very good.  All polarizing glasses perform one function.  Perhpas the
seat of the judges (distance from the screen) might be a better variable
to compare with.  And you are right, this is not specified. 

The bottom line for me is that the best viewing devices should be
available when judging stereo cards and the judges should be encouraged
to use those.

-- George Themelis


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