Archived posting to the Leica Users Group, 2000/03/06
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- -----Original Message-----
From: owner-leica-users@mejac.palo-alto.ca.us
[mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf Of
drodgers@nextlink.com
Sent: Tuesday, March 07, 2000 1:54 AM
To: leica-users@mejac.palo-alto.ca.us
Subject: [Leica] Re: 50mm f1.5 Nokton question
B. D.
>>I'm curious...How does one calculate these "stop fractions?"<<
I'm sure that someone has already answered this, but f-stops are based on
natural logrithms. You can use a scientific calculator, a spreadsheet like
Excel, or you can even look up the codes in the tables of an old algebra
book.
If you really want to go retro, you can borrow my slide rule. I just ran
across it the other day. It brought back memories of not that long ago. I
found it in a box with my Hendrix ("Purple Haze") album and my High School
Diploma.
David.