Archived posting to the Leica Users Group, 1997/03/13

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Subject: Re: OFF TOPIC--Englarging lens questions
From: gmrobinson@mmm.com
Date: Thu, 13 Mar 1997 08:20:14 -0600

At 06:55 AM 3/13/97 -0400, you wrote:
>What, if any, practical effect does the aperture setting of a enlarging 
>lens have? If you print a negative at f/16, will you have a greater 
>"depth of field" in the sense that if the negative is not perfectly flat 
>in the carrier, that area of the negative will print sharper than if you 
>printed the same, not-perfectly-flat negative at f/2.8?
>
>You are correct about the depth-of-field.  However, diffraction (a lens
aberration) of the image increases as the aperture becomes smaller
resulting in less sharpness.  F8 is the best lens aperture for most 50 mm
enlarging lenses.  Use your timer to adjust the exposure instead of the
aperture.

Glen Robinson