Any lens that is good at f/1.2 will only get better stopped down, aspherical
elements or not. With the exception of molded aspherics and faster computer
modeling, everything available now was available to OM lens designers,
generally. In fact, the selection of glasses was better back then, as there
were more leaded-glass formulations available. Recently some of those have
been eliminated, to the detriment of lens design in some cases.
The upside of aspherics in many cases is the reduction in number of elements
needed = better contrast and correction (for a given number of elements),
and additional degrees of freedom as a result.
On 4/12/12 6:16 AM, "olympus-request@xxxxxxxxxxxxxxxxx"
<olympus-request@xxxxxxxxxxxxxxxxx> wrote:
> Agreed. But having the option of using aspherical elements has opened
> the door to other lens design options. The see-in-the-dark lenses are
> a very good example of this. You can design a lens to perform
> admirably at F1.2, but really sucks pond water stopped down. Or you
> can have a lens that performs great stopped down but stinks when shot
> wide-open. Being able to incorporate newer optical technologies like
> aspherical elements and low-dispersion glass has given the designers
> the ability to create a lens that is decent across the entire intended
> usage range--not just in a narrow usage. Lens design is all about
> compromise, though. Something has to give.
--
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