Re: [Leica] Tri-Elmar and Depth of Field marks

["John Hudson" <jahudson@direct.ca>]

- -----Original Message-----
From: Richard J. Wyble <rwyble@erols.com>
To: leica-users@mejac.palo-alto.ca.us <leica-users@mejac.palo-alto.ca.us>
Date: Monday, June 14, 1999 7:22 AM
Subject: Re: [Leica] Tri-Elmar and Depth of Field marks


>Excerpts from leica: 14-Jun-99 Re: [Leica] Tri-Elmar and D.. Martin
>Howard@ikp.liu.se (657*)
>
>
>> "Hyperfocal" means the point at which as much as possible will be in
>> focus (i.e., maximum depth-of-field).  Since a great deal lies at
>> infinity (and beyond ;) the hyperfocal distance is the distance which
>> covers "infinity" and as much infront of "infinity" as possible.
>
>This I understand. My question therefore seems to be how does one
>calculate or even estimate just what that "as much infront of 'infinity'
>as possible" might really be?

Shouldn't the question be posed as "how far in front of me does infinity
start for any given aperture?" For example, using my 50mm Summilux, at f16
the maximum depth of field is from 8 feet to infinity. At f11, maximum depth
of field is from 12 feet to infinity. Judging this kind of short distance is
relatively easy.

jh



>  rwyble@erols.com
>  Richard J. Wyble
>
>