[rollei_list] Re: Rollei 35S, SE

The modern Cosina/Voitlander Heliar 50/3.5 is purported by at least
one of the test magazines to be one of the best corrected lenses in
all of 35 mm photography. It is supposed to have it's best corrections
wide open... f/3.5 is its true design speed for this format...


Eric Goldstein

--

On 9/27/07, Richard Knoppow <dickburk@xxxxxxxxxxxxx> wrote:

>     Altman claims in his patent (USP 2,279,384) that the
> extra element is used to control "rim rays", in other words
> to make the lens sharper when used at large apertures. Kodak
> made a series of lenses based on this design including the
> 50mm and 75mm Enlarging Ektars.
>     The Heliar type does not seem to have been very popular.
> It was exploited by Voigtlander, who held the original
> Harting patents and to some extent by others. Probably the
> most familiar beside the Voigtlander Heliar is the Pentac of
> Dallmeyer designed by Lionel Booth.
>     Cemented lenses were popular with designers before lens
> coatings became available because they are a way of reducing
> flare. Once good coatings were available air spaced designs
> displaced most of the older cemented lenses.
>     From what is in lens design books the Heliar type has
> some inherent problems which probably also account for its
> lack of popularity. The Voigtlander Apo-Lanthar is another
> Heliar type.
>
> ---
> Richard Knoppow
> Los Angeles, CA, USA
> dickburk@xxxxxxxxxxxxx
>
> ---
> Rollei List
>
> - Post to rollei_list@xxxxxxxxxxxxx
>
> - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe'
> in the subject field OR by logging into www.freelists.org
>
> - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with
> 'unsubscribe' in the subject field OR by logging into www.freelists.org
>
> - Online, searchable archives are available at
> http://www.freelists.org/archives/rollei_list
>
>
---
Rollei List

- Post to rollei_list@xxxxxxxxxxxxx

- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' 
in the subject field OR by logging into www.freelists.org

- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 
'unsubscribe' in the subject field OR by logging into www.freelists.org

- Online, searchable archives are available at
http://www.freelists.org/archives/rollei_list

Other related posts: