[Leica] coated vs multicoating

["Birkey, Duane" <dbirkey@hcjb.org.ec>]

Multicoated lenses would fall under the classification of coated lenses....
The only way you'll ever know if he meant single coated is if the author
says specifically that the lenses were single coated....  But authors are
known to be wrong at times especially if they base info on second-hand (or
third and worse) knowledge.

I'm not sure whether one can judge whether something is multicoated or
single coated based on the color of reflections as a number of variables as
to the type and thickness..... But some lenses are a mix of single and
multiple coatings....  One should be able to compare both CL and CLE lenses
and see what differences or similarities  there are in the reflections....
Neither would be conclusive..... though  

I've always been suspect of lens diagram drawings.....  as one wonders
whether they were drawn for marketing purposes or are based on a actual
cross section of a lens....   or if they were a design proto-type as opposed
to the actual lens, or mis-info to throw competitors a curve in their lens
design.  The only way you'll know whether the lens matches the diagram is to
cut it in half....  Canon has had examples of their aspherical technology in
their brochures that don't match the actual lenses.

Let's be honest, How many people in the world can look at a cross section
lens diagram and tell you how well it will perform... I'd guess Zero...  But
I've been wrong before. 

The same goes for coating to some extent,  you'll have to trust the
manufacturer and the people who coat the lenses whether it is a singular or
"mulitple" coat... and then whether a slight variation in coating
constitutes an improvement in performance or is done for cost savings.  

When I worked in photo retailing... we had a couple customers who wanted to
know the number of elements and the formula of every P&S in the store...  my
boss finally asked him how elements he wanted... at which point... he
started looking at features and how they handled... and left the store
without buying anything....  He was one of those customers that we would try
to go on lunch break whenever we saw him coming.... I learned to pause, look
around the store and out the window before letting one of our employees
leave on break.  

Duane 




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*
I've re-read the CL tests by Modern and Popular Photography,  neither of
them
mention multi coating.  Even though Theo Kisselbach's book "Leica CL" is
quite
definite about the CL lenses being "coated," there is no hint of better
coating or
coating improvements, nor is there any mention of multi coating.  If
Kisselback
doesn't know the CL lenses are multi-coated, its very difficult to believe
they are,
regardless of any claims to the contrary.

Stephen Gandy