Olympus-OM
[Top] [All Lists]

Re: [OM] anodized titanium; OTC metering; resolution vs format size

Subject: Re: [OM] anodized titanium; OTC metering; resolution vs format size
From: Matthias Wilke <Matthias.K.Wilke@xxxxxxxxxxxxxxxxxx>
Date: Tue, 16 Feb 1999 23:57:05 +0200
William wrote:

>At the risk of offending those who went to the trouble of answering, I
>must point out that the answers given about why small-format lenses can
>(seemingly) supply higher resolution haven't answered anything. The
>resolution of a smaller image does not necessarily scale with the image
>size, and simply _saying_ that a smaller area allows for better
>correction is tautological.
>I'm still looking for an answer. If anyone finds it, I would be very
>grateful. I'm going to pull out my Focal Encyclopaedia and Neblette and
>do some searching.

I'm not an optical engineer, but when reading in a very interesting book
about microscopy from the former DDR (east German republic), "Handbuch der
Mikroskopie" by Beyer and Riesenberg, there were comparisons between the
flat pictured fields of top lenses  of different eras (ages). The greater
the flat pictured area the newer was the construction. What I want to say
with this example is, that it seems to be indeed a problem to achieve an
equal correction over a wide flat area. If this is the case, one can
imagine, that if the covered field can be small (not desirable with
microscopes) the lens can be corrected for other purposes than a great
field. Another example are the world's first apochromatic microscope lenses
by Zeiss, which were engineered by Ernst Abbe circa one hundred years ago.
These lenses were excellent and apochromatic in the middle of the field,
and toward the edges the quality decreased. Nowadays, you can buy wide
field, flat apochromates, which show no degradation of the picture quality
toward the edges, but one hundred years ago, those lenses were state of the
art. I think the above is also no explanation ?

Matthias



< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >


<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz