P3D Re: Viewer adjustments

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

>>I will introduce a new stereo viewer with a control that allows you to
>>move the lenses vertically, to satisfy those who cannot mount well
>    
>Sorry George but believe it or not its actualy been done !. Some time ago
>I bought a fairly cheap (In Both senses of the word) viewer for 2x2 pairs
>as well as being able to adjust the interocular there is a little screw
>that allows one of the slides to be slid up and down. 


Yes, thanks Peter!  I have one of those too!  They were sold by Porters
in the late 80s.  They came with three pairs of 2x2 slides, examples of 
normal, hyper and hypo stereo.  I still have everything.  The viewer was 
made in Italy.  Later, another similar viewer came from Italy but did not 
have this screw.  I had people asking for the old one because they want to
be able to adjust the slides vertically.  I think it was a useful feature 
for previewing single SLR point-and-shift stereo pairs.

>"This is the proffesional
>solution  to the problem of giving optimum viewing of stereo pairs which
>have not had time consuming adjustments made to them during mounting". 

Aha!  This reflects the two different philosopies:

1. Align slides during mounting
2. Align slides during viewing/projection

Sure, #1 takes some time but you have a perfect pair to be viewed with any
system.  #2 requires that each viewing/projecting device is adjusted for
each individual slide and the eyes subjected to constant misalignmnents
and corrections.  What a pain!

George Themelis


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