[Leica] New Generation Cosina RF/VF & reported Epson RD-1 focusing problems

[leicanikon at earthlink.net (Stephen Gandy)]

Hi Karen,

I don't believe it's a good idea to lump all versions of Cosina's rangefinder
mechanisms together --  there are differences in the now four generations.
the statement about "The R2 that the R-D1 is based on has a fragile RF too"
simplifies to the point of being inaccurate as far as I am concerned.  On top
of that is the question of what is really causing the reported RD-1 focusing
problems

As I do warranty work on the entire Cosina Voigtlander Bessa series, I can
assure you the later R2/R2S/R2C series cameras have considerably less RF
alignment problems than Cosina's first combined RF/VF, the Bessa R.     Even
so, the R remains a bargain to me considering the low closeout price.   Oddly
enough my personal Leica M6 Titanium classic needs RF alignment annually, but
so far my personal Bessa R2 never has need RF adjustment -- go figure.  I am
just saying the different Cosina made Bessas RF/VF should not be lumped
together in terms of durability.  The very differently designed Bessa T
rangefinder mechanism has also proven durable in service with a minimum of
problems.

Cosina's new generation of RF/VF found in the Voigtlander  R2A & R3A / Epson
RD-1 / and upcoming Zeiss Ikon all use a new updated and modified version of
the R2 finder.   True they are related to the R/R2, but the new designs are
significantly different.  New RF/VF family improvements include a larger
eyepiece ocular for better eye relief and an approximately 50% larger RF 
patch
for easier focusing.  Additional family differences are the 1:1 life-size
finder in the RD-1 and R3A vs the standard .7 magnification in the R2 and 
R2A,
as well as the long 75mm base length in the upcoming Zeiss Ikon.   Knowing
Cosina, I am sure internal design improvements over the R2 are likely
incorporated in the new designs as well.    While troubles have been reported
with the Epson RD-1 rangefinder, the new design will probably mean improved 
RF
durability once initial  production bugs are worked out.  It also needs to be
pointed out that the cause of some reported RD-1's focusing errors  has  not
been determined.   Is the problem RF adjustment, sensor placement, user 
error,
a combination of the above, or something else?

While the new Cosina RF/VF designs are not as good overall as the RF/VFs in
today's Leica M rangefinders,  the new generation Cosina RF/VF finders come a
lot closer than many would expect.   My point is that we can't be sure what 
is
causing the reported RD-1 focusing problems without careful tech examination 
of
several such cameras, and that treating all the Cosina Voigtlander RF designs
like they are same in terms of design or durability simply does not give an
accurate picture ...  (OK, so I love photography puns)

Stephen

Karen Nakamura wrote:

>  The R2 that the R-D1 is based on has a fragile RF too. They tend to
> drift out of calibration if they are handled roughly. You can
> recalibrate it yourself if you know how but it's not as simple as the
> old Leica screw rangefinders.  You have to take the top off. My guess
> is that Epson will do this for free during the warrantee period, but
> you'd have to take it in.
>
> Epson should use strong lacquer when gluing down the calibration
> screws. It's not like the cameras are broken, but it's definitely a
> pain when your RF drifts.
>
> Karen