[photo-3d] Different Realists

["Dr. George A. Themelis" <drt-3d@xxxxxxx>]

>Double exposure prevention.
>DOF scale.
>Down instead of up exposure counter.
>Shutter speed increase.
>Different lens cover.
>At least 6 different lenses.

Chuck et al.,

You have to realize that David White introduced three
officially different Stereo Realist models:  The 3.5,
the 2.8 and the Custom.  In order to justify the
higher prices asked, DW had to put new features to
the more expensive models.

So, going from the 3.5 to the 2.8 it introduced:

- Double Exposure Prevention (DEP)
- DOF Scale
- Higher shutter speed from 1/150 to 1/200
- Different lenses (4-element 2.8 vs. 3-element 3.5)

As it turns out, the DEP and DOF were soon built
in the 3.5 models as well.  The 1/200 shutter speed
was achieved with the same exactly shutter (Ron Zakowski
can increase the tension in the 3.5 spring to achieve
1/200.  He also sells DOF scales and will do the DEP
conversion).  So basically the only difference of any
importance is that the 2.8 has different lenses, which
justifies the designation as a different model and
the higher asking prices today.

The lens cover change happened when the dies were
damaged and new dies where made.  Note that the 
2.8s have the same cover as the 3.5s with a "2.8"
stamped in it.

The count-down counter is only found in the Custom.
The Custom also has a few more differences compared
to the 2.8/3.5 models.  Again, this was done to
justify the different model number and the higher
asking price.

The lens suppliers were changed in the 3.5 and 2.8,
dictated most probably by financial considerations
(original lenses were too expensive) and not by an
effort to improve the camera.

If you step back and think about it, it is remarkable
that the Realist was kept the same in 25 years of
production.  The 2.8 and 3.5 bodies are essentially
the same.  The Custom body has only a few changes.
Even the Realist Macro body is the same design, that's
why David Burder is buying Stereo Realist bodies to
convert them to Macro Realists.

Overall it is remarkable that no substantial design
changes were made in 25 years!

George Themelis