Archived posting to the Leica Users Group, 2000/03/06
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]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!