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] Re: 50mm f1.5 Nokton question
From: "B. D. Colen" <bdcolen@earthlink.net>
Date: Mon, 6 Mar 2000 21:08:59 -0000

Thanks, David - I've learned far more today about f stop calculation than I
ever wanted to learn...:-) But I sure am glad to hear you found your Hendrix
album..!

B. D.

- -----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.