P3D Re: "Cheap" new lenses VS. "Quality" new lenses

[Eric Goldstein <egoldste@xxxxxx>]

Johnson, Stuart wrote:

> An Olympus 24mm lens with a 2.4 aperture
> is going to be better than the same at a 2.8 or a 3.5 aperture.  Sure,
> most of us probably shoot between F8-F16 to assure depth of field, but
> the "faster" the lens is, the BETTER the quality of glass, construction,
> etc.
(snip)
> There is simply no comparison in my estimation between a modern lens
> and an older (50's type or earlier) lens.  Simply put, if they were THAT
> good, they would still be manufacturing them.
(snip)
> However, years ago, I remember listening
> to a guy that owned a large camera shop explaining those exact differences.
> There are many reasons why the "current" lenses are better (as he said).
> This was from a guy who spent his whole life involved in photography.

Hi Stuart-

I'm afraid there is a lot of mythology and misinformation with regard to
lens design, modern glasses and coatings, and exactly what you are
getting when you pay those premium prices for faster lenses. Suffice it
to say that a camera shop owner is probably a poor source of reliable
information - - I deal with professional equipment outfitters all the
time, and they know or care little about the actual performance of the
gear they sell or rent, only what the profit margins are from the
difference suppliers.

Lens performance is a complicated area and if you are interested in
gaining some good general information to build some expertise at no
cost, I'd suggest a search of the photo-3D archives. Bob Howard has been
a student of optics and lens performance for some 50+ years, and he has
contributed some extremely informative posts to this list on this very
subject. Suffice it to say, although modern materials, designs and
production techniques could yield remarkable camera lenses, the vast
majority of them are no better corrected and often quite a bit worse
than some of our 50s lenses at the apertures we use because the
manufacturers have no incentive to produce these more highly corrected
lenses and in fact have every incentive to make crappier ones. As George
T correctly points out, those faster lenses you are paying a premium for
are likely no sharper than our 50s glass at f/8 or smaller, though they
may exhibit higher contrast and so may be more appealing to your tastes.

There are exceptions, and I mentioned one in my last post on this
thread, the modern Zeiss Tessar 35mm f/3.5 used on Yashica T4s. May your
SLR lens be this good, I don't care what you paid for it. The 38 mm
Zeiss Sonnar f/2.8 used on the Contax Ts are also outstanding, but their
numbers are extremely close to the Tessars and the cost differential is
substantial. Both of these lenses are non-retrofocus, BTW.

Also in the "you get what you pay for...NOT" category I will also throw
in the fact that one of the most highly corrected lenses I have ever
used is a Canon FD 28 mm f/2.8 which cost about a hundred bucks new some
18 years ago. The lens is virtually distortionless and almost scarily
flat field with outstandingly even illumination to the corners. I have
absolutely no idea why it is as good as it is, it is not fast or exotic
or expensive. I guess the computer came up with a killer design that
day...


Eric G.


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