Archived posting to the Leica Users Group, 2000/03/06

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

Subject: Re: [Leica] 50mm f1.5 Nokton question
From: Marc James Small <msmall@roanoke.infi.net>
Date: Mon, 06 Mar 2000 13:54:13 -0500

At 10:17 AM 3/6/2000 -0700, John Collier wrote:
>This from a long time ago, with my memory that is about a week, but I
>thought it went:

The surface of a circle is pi x radius squared.  I don't have lenses at
hand, but roughly, the putative radius of a 50mm f/1.4 lens is 17.86mm,
that of an f/1.5 lens is 16.66mm.  Squaring these, the ratio is 318.9:277.56.

Reducing this gives 1.14, or 1 1/7.

Mayhaps my math is way off?

Marc

msmall@roanoke.infi.net  FAX:  +540/343-7315
Cha robh bas fir gun ghras fir!