Archived posting to the Leica Users Group, 1997/10/02

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: f/stops weird and wonderful
From: Robert Sproul <sproul@sc.edu>
Date: Thu, 2 Oct 1997 08:43:03 -0400

>At 09:50 AM 10/2/97 +0200, Alf wrote:
>> .. 2.2, 3.2, 4.5, 6.3, 9, 12.5, 18, 25 ..., with an additional mark at
>>f 2.9 for the Agfacolor filter in the early 30ies.
>
>
>There are minor variations on the Stolz scale:  I have lenses which are
>marked f/12, others f/12.5.  I believe the markings on the Summar are more
>accurate than the list I posted.
>
>The Agfacolor system was the first commercially available colour system.
>It mandated the use of special filters both to take and to project the
>slide.  The system was only sold for a couple of years before Kodachrome
>and its ilk came on the market, though Leitz and several other
>manufacturers built a fair number of lenses to accomodate it.
>
>Marc
>
>
>msmall@roanoke.infi.net  FAX:  +540/343-7315
>Cha robh bas fir gun ghras fir!

	Just my own curiosity-is there further info on the Agfacolor
system? I have a Summar with the tabs(?) for this filter. I have seen
references to this system but I don't know any details. BTW, the appendix
in Mr. Small's latest book concerning our "throw-away" mentality is very
worthwhile reading.




Robert Sproul

sproul@sc.edu