Received: from zonker-fddi.hpl.hp.com by opus.hpl.hp.com with SMTP (1.37.109.8/15.5+ECS 3.3+HPL1.1) id AA08914; Thu, 29 Sep 1994 16:44:38 -0700 Return-Path: <poulton@zonker.hpl.hp.com-DeleteThis> Received: by zonker.hpl.hp.com (1.37.109.8/15.5+ECS 3.3+HPL1.1) id AA27135; Thu, 29 Sep 1994 16:44:32 -0700 Date: Thu, 29 Sep 1994 16:44:32 -0700 From: Ken Poulton <poulton@zonker.hpl.hp.com-DeleteThis> Message-Id: <9409292344.AA27135@zonker.hpl.hp.com-DeleteThis> To: wind_talk@opus.hpl.hp.com-DeleteThis Subject: Re: Re: Re: 3rd ave sensor design
> The entire target would spin, like those signs you see in front of
> stores. What the detector would see is the difference between front and
> back (white and black) of the spinner, not the difference between
> spinner and background. Depending on the sensor (and post processing)
> the target would not need to fill the field of view.
The point is that even huge spinner cups (6" diam) are incredibly
small from a mile away. The background problem is everything *around*
the marker (water, far shore, etc). Even when you look through binocs,
the channel marker is a tiny part of your field of view (.07 degrees
through 12x binocs). The fluctuation of light from the spinner would be
a tiny fraction^2 of the total light at the sensor.
Ken Poulton
poulton@opus.hpl.hp.com-DeleteThis
"If you're not part of the solution, you're part of the precipitate."
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