Viewer prices and a bit more...

[P3D Dr. George A. Themelis <fj834@xxxxxxxxxxxxxxxxxxxxx>]

The question of monetary value for stereo slide viewers is appropriate and
it can be discussed here.  (Only postings selling or buying stereo items
are appropriate for sell-3d).

When discussing the value of used equipment have in mind that the prices
paid depend on factors like demand and supply and on the mood of the buyer
and seller at the moment of the transaction.  With this in mind, here are
my comments regarding the viewers in question:

1) TDC stereo Vivid:  This is a rather rare viewer in high demand by
owners/collectors of TDC cameras and those who think that this viewer is
better than the Realist red button :).  In my mind, the TDC "Deluxe"
optically is in the same league as the Revere 22 and Realist red button. 
Mechanically, it suffers from one major flaw:  The focusing rack is made of
plastic which it is part of the bottom case, while the focusing pinion is
metal.  I have seen many viewers where the rack is stripped and the viewer
cannot focus properly.  Since the rack is part of the viewer's body, I have
not figured yet a way to fix it.  Be careful to exmine the viewer before
buying or reserve the right to return it or renegotiate the price if it has
this problem.  A good TDC Vivid viewer is worth $125 to $175.  Rarity might
drive this price higher if found in box, w/instructions, etc.  Note that
TDC also made a simpler viewer (single-element lenses, no interocular
adjustment) which is also hard to find.

2) Revere stereo 22:  Good solid viewer with good lenses.  In good demand
by Revere camera owners and those who think that it is better than the
Realist red button :) :). Light reflector sometimes is damaged or tends to
cast shadows.  Metal Revere logo is usually missing (this is glued in the
plastic switch button).  Value: $100-$175, depending on condition. The
Wollensak viewer is identical in appearance (except for the color, brown
for Revere, black for Wollensak, and the logo) BUT the lenses are different
in the two viewers.  Some stereo photographers swear by the lenses of the
Wollensak (they think they are better than the Realist red button :) :) :))
and this fact, in connection with the rarity, has driven the price of the
Wollensak to $200 and up.

3) Brumberger:  Second-class viewer but solid and reliable, with a long
production history (the Star D II viewer sold new from Reel 3-D today is
made from the same dies.)  It has a simple screw-type focusing mechanism
and no interocular adjustment.  Lenses are plastic, even though in earlier
viewers they are thick glass.  Value: $30-$50.  Good choice for a lighted
focusing second viewer or to give away to a beginner stereo photographer.

4) Kodaslide I:  Kodak made two viewers:  Model I and model II.  Model II
has achromatic lenses and came with AC components as standard.  Model I has
plastic lenses (the worse lenses ever put in a viewer for some people) and
was sold without the AC components (these were available as an option). 
This was Kodak's way of attracting low-budget buyers into 3d or those who
were looking for a cheap second viewer, to give away, etc. (selling price
of model I, was half that of model II).  Appearance-wise the two viewers
look identical except for the model number which is on a metal plate by the
interocular adjustment.  They also share the same mechanical problems,
mainly "frozen" focusing adjustment.  Value: $40-$90.  Some people have
paid $100 to buy this viewer but for this price you can almost get a
Kodaslide II ($100 to $175).  Recently, Elliott Swanson and Alan Lewis have
replaced the lenses in the KI viewer with Wollensak lenses.

All these viewers can benefit from a bright halogen bulb (do I need to tell
you where to get it? :)) and cleaning of the switch contacts to eliminate
light flickering.  Cleaning the lenses is also recommended but be careful
with the plastic lenses of the Brumberger and Kodaslide I.  Regarding 7p
viewing capability, the Kodaslide I can be modified to show 7p, even though
it is questionable whether you want to see beyond 5p with the quality of
these lenses.  The other three viewers are 7p, at least in theory.  In
practice it is a good idea to open the apertures a bit to view 7p without
distractions.

Final note:  The viewers with achromatic lenses from the 50s (Realist, KII,
Revere/Wollensak, TDC...) are the best stereo slide viewers ever made, both
optically and mechanically.  Nothing made new today matches this quality. 
RBT is making cameras, projectors, mounts, but has not touched the viewers
(except for a cheap cardboard one). Price is an issue (considering that a
pair of good achromatic lenses from Edmund Scientific costs $80+) but cost
has not stopped RBT from making $3000+ cameras and projectors.  This, in my
mind, propagates the misconception that viewers are secondary in the
enjoyment of stereo photography.  VIEWERS ARE VERY IMPORTANT for both
stereo photographers and collectors of stereo images!!!

For more information on stereo slide viewers, quality of lenses, how to
tell achromatic lenses from single-element lenses, maintenance, etc., check
a series of articles in Dalia's "Inside 3-D" mini-magazine, by the one and
only "King of Stereo Viewers", our own Dr. T.

With humble regards -- George Themelis


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