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Re: Aquatic Plants Digest V4 #491

To: Aquatic-Plants at actwin_com
Subject: Re: Aquatic Plants Digest V4 #491
From: Dave Gomberg <gomberg at wcf_com>
Date: Tue, 22 Aug 2000 21:26:06 -0700
In-Reply-To: <200008221821.OAA07552 at actwin_com>

At 02:21 PM 8/22/00 -0400, David Focalpoint wrote:
>What in the WORLD is a difference in lighting less than
>1/4 an f-stop mean in relation to aquarium lighting please

An f-stop is a factor of 2 (100% increase).
One quarter f-stop is a factor of 1.19 (a 19% increase).

Wars have been fought over less.  A 19% increase is what you get from 
adding a fifth tube to a four tube fixture (figuring in obstruction 
issues).  If choosing one reflector over another, 19% is a huge difference.

--
Dave Gomberg, San Francisco            mailto:gomberg at wcf_com
NEW Planted Aquaria Magazine:        http://www.wcf.com/pam
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