Hello Patrick,
There is no doubt that advances in technology have improved the quality
of both prime and zoom lenses, and it is probably best to address them
separately.
If you compare the early Nikon primes to the latest versions two things
become evident. The new lenses are lighter and smaller. The first is the
result of the breakthroughs in materials science in the interval. The
second is from equally stunning developments in the science of optics.
But, the improvements in optics may or may not have contributed much to
the performance in prime lenses. There are many fine lenses being
produced today, and not all of them "shoot down" the early Nikkors.
Lighter
and smaller is certainly handy, but performance is still the key.
I don't know if computer aided design has been as beneficial to the
advanced design of zooms as is the progressive developments in the
science of optic design as some would think. I say this from a
background in mechanical engineering, specifically in military flight
and weapons systems. We embraced CAD/CAM like a lost love, and over a 15
year period development, our designs always demonstrated the
improvements in the state of the art, but did not always reflect the
contribution of CAD. Our design groups produced phenomenally successful
designs (you saw most of them in Desert Storm, and the continuing
skirmishes), one after another, despite a 15% reduction in productivity
from failures in hardware, software, and training; that problem stays
with us like a bad cold. If I was to guess at the most important factors
contributing to better lenses, I would more likely cite the
breakthroughs in materials science, improvements in machining process,
and the evolution of optic designs and coating processes being
responsible for the dramatic improvement in zoom lenses, than I would
computer aided design. Remember that the Saturn V, Boeing's 747, and the
Shuttle all began on the board.
As to the use of plastics (or more properly composites), they do make
lenses lighter, and lighter lens components mean faster AF, and faster
AF seems to be where Nikon is heading. My first AF Nikon lens was the
obligatory 50mm f1.8, and it seemed a toy compared to metal lenses. I
never thought that I would ever buy another lens with a composite
chassis. It was the 24-50mm f3.3-4.5 AF that convinced me that I was
wrong, and that composite materials were here to stay. That is one
sharp, highly flexible lens that comes closest to what I think the
"normal" lens should be. So much so, that it now lives on my F3. Talk
about "Mutt and Jeff" combination! Imagine my F3, with the MD-4
attached, and a composite lens that weighs less than a pound. Oddly
enough, it handles very well. I only wish I had that lens back when I
shot for the paper.
Adios,
Bill Hilburn Jr.
Patrick Warnshuis wrote:
>
> Re: comparing performance of older MF lenses with
> newer AF lenses.
>
> Thanks, Bill for the construcive response. It would
> appear that the discussion should be differentiated
> into two distinct areas: comparison of primes and
> comparison of zooms. Both should make fascinating
> discussions.
>
> I presume that zoom technology and performance has been
> greatly enhanced by the advantages of computer-aided-
> design so that GENERALLY the later zooms would show a
> performance advantage over older ones with select
> exceptions. And again, here we must identify our pre-
> ferences based on strictly image improvement as opposed
> to mechanical construction, feel, etc.
>
> The area of prime lenses should pose a more difficult
> area of inspection as CAD is not as important a factor
> due to simpler groups and elements.
>
> Aside from CAD, has there not been an improvement in the
> glass itself, in the availability of higher quality products
> to the mass markets, in manufacturing and assembly
> improvements?
>
> Is plastic really such an anethema to image results?
> I suspect one engineering design consideration with respect
> to the newer AF lenses is that they MUST be lighter to
> reduce inertia and resistance for faster, more accurate
> positioning, both features demanded by users. Yet these
> same users resist the resultant 'feel' of the newer lenses.
> And, obviously, in order to meet the demands of faster and
> more accurate AF, the throw of the focus ring and its feel
> will not compare with the needs for MF so that the AF lens
> operated in the MF mode will not replicate the feel of a MF
> dedicated lens.
>
> Henry, from Down Under, provided the most direct response to
> my original question: "You've got the lenses. Go shoot and
> compare." Yup, that will answer my immediate questions about
> my specific lenses but I'm intrigued by the more general
> consideratons as well.
>
> ....patrick
