[Leica] noctilux factoid of the day

[henningw at archiphoto.com (Henning Wulff)]

At 5:05 AM -0700 4/25/08, Frank Filippone wrote:
>Good point......  Not so sure about the use of adding machines in
>engineering circles......Persona;;y I never saw them used in that
>environment, nor my Dad... who was a Civil Engineer starting in 1941.
>
>I think that adding machines again were an accounting issue, not an
>engineering issue..... but I am not sure
>


In the early and mid sixties when I was studying physics in 
University we used a lot of the mechanical calculators (essentially 
sequential adding machines which produced the functions of 
multiplication and division). If you needed more accuracy than 3 
digits you used those, or log tables, which got you a couple more 
digits.

The problem with computers at the University in the early 60's was 
that you wrote your program, produced your stack of punch cards, took 
them to the computing department, left therm overnight, and came back 
in the morning to a pile of paper that represented the unresolved 
loop you accidently wrote into your progaram. Debug, and do the whole 
thing again. It could easily take a week to produce a single 
functional short program. With a slide rule and mechanical calculator 
you were usually way ahead.

The first Noctilux, the f/1.2 aspheric was probably designed with the 
help of mechanical calculators such as the Friden, as you need the 
accuracy which slide rules can't provide. The current Noctilux, the 
f/1, was most likely designed (in Canada) with the help of computers.


>Of course there are and were tables.... books of logarithms ..... that were
>used.  Calculating Square Roots using tables is quite trivial....
>
>Frank Filippone
>red735i@earthlink.net
>
>
>Have you guys never heard of Friden or Marchant desktop calculators?  These
>were way more accurate than my old K&E slide rule.  Friden even made one
>that calculated square roots.  All of the checkpoint calculations for our
>digital data reduction programs were done by hand by some talented ladies
>using these machines.
>
>Jim Nichols
>
>
>
>
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    *            Henning J. Wulff
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