[Leica] Lenses for M6

[Denis Boisclair <denis.a.boisclair@lineone.net>]

Many thanks to everyone who replied to my posting concerning which 
used  lenses which would  activate the 35 mm viewfinder frame in the M6.

  It appeared that with a number of 1273923, indicating a manufacture date 
of 1955 - when only the M3 ( which didn't cater for  a 35mm frame) was 
around, the Summaron 'M' lens, which I had ordered - but not yet received - 
would only activate the 50mm frame.Now  that it has arrived  it does in 
fact  - to my great relief bring up the 35mm frame!! Must it have been 
modified?

While on the subject of lenses I would like to raise two points:-

(i)Although there are Leica lenses, which have been improved upon several 
times since they were first introduced( I believe there are at least  two 
subsequent versions of my  1959 Summicron  'M' 50mm f 2.0 lens) their name 
remains unchanged and they are not   given any distinguishing reference, as 
is the case with a Canon lens which I have and which is designated' Mk 
III'. However, when these lenses are advertised, often the number is not 
quoted, so that even if a prospective customer has(a)a list of all the 
numbers and corresponding years (b)knowledge of when the changes took 
place(c) test reports on each version -  how are they supposed to know the 
exact quality  and value for money of the lens in question??!!

(2)There has been some recent discussion of some lenses being labelled as 
'dogs'. I have often wondered exactly how  much importance 'weaknesses' in 
lens performance should be given by a prospective buyer, who may not be 
interested in producing enlargements greater than 12"X 8" - and  even only 
7"X5" for the bulk of his shots! Color rendition will obviously be 
important for any size print ,but could it not be the case that for 
resolution quality -  or 'sharpness' -  comparisons between lenses might be 
based on 'over the top' criteria for many users - unless perhaps high 
quality screen images from projected slides are important?

Denis