[Leica] Leica, Process control, and Minolta bodies

["Frank Filippone" <red735i@earthlink.net>]

..... No they do not cost the same, but
>not because of MORE  rejects, but rather because there are stricter limits

It is NOT an erroneous statement, because this is a reality. Leica rejected
so many CL cameras, that Minolta gave up doing them. Zeiss rejected so many
of their own Contax 80-200 f/4 lenses (which was a wonderful lens that
could focus right down to the front element) that it cost 8-10 times the
competition at the time. High rejection rates are well-known.



I think you missed the point....it is really a volume thing..... the rejects
are caused by a too wide variation in individual piece part manufacturing
tolerances to specification.  These tolerances build up and eventually get
out the finished goods out of spec.  Manufacturing process control for the
past 15-20 years states that you never allow the final product to get out of
spec, you catch the errors or tolerances at the piece part point.  These
tolerances at the piece part point must be tightened ( which costs more on a
per unit basis, and really costs more if you are doing very small runs plus
the R+D costs to do this when amortized over a small volume) ) such that the
final assembly is within spec.  When this is done, you tighten the specs
again.  The idea is to never throw out a single part along this learning
curve, you just make them more perfectly each time you make a run of parts.
Continuous process improvement.  The final result is that the final assembly
has reached extremely low tolerances, therefore low reject rates.... but it
takes volume and focus.  I do not think that Zeiss or Yashica/Zeiss rejected
the completed lens.  They are familiar with manufacturing techniques and
especially process control.  They never made enough lenses (enough
iterations)  to figure out the problems and resolve the solutions.

A rule of thumb is that your manufacturing costs should go down at the rate
of 25% per doubling of volume, as expressed in units per constant  time
period.

The example of Leica/Minolta and the CL is real good.. the big house could
never spend the effort ( resources ) to locate and get in control the
manufacturing tolerances... too small a production in an otherwise enormous
factory..... it was doomed to fail.  The same may be true of Zeiss and
Contax.  An interesting idea would be to take a MInolta body and change ONLY
the lensmount and necessary prongs to accomodate the Leica R lenses.  Given
the S series of lenses this may not be as difficult as it first
looks......Or, (Oh, the flames I may receive for this!) change the
mechanical properties of the Leica Lenses to fit on a Minolta (Canon, Nikon,
or other )  body.  Keep the optics just like they are today.  Now there is
an idea!  Leica optics on Nikon ( or other) body reliability!

Final note.... While most of the process control improvement theorems were
based from the USA, the experts in the implementation are Japanese.  They do
understand the issues, but can not break the inevitible low volume issue
with Leica et al.

Frank FIlippone