<br><br><div class="gmail_quote">On Thu, Jan 28, 2010 at 6:03 PM, Michael Mol <span dir="ltr"><<a href="mailto:mikemol@gmail.com">mikemol@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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The chief problem with "darkvision" as it applies to passive near-IR is<br>
that there is a lot of ambient near-IR radiation that's not related to<br>
warm bodies.<br>
<br>
In short, your warm body radiation in the near-IR will be there, but<br>
largely drowned out by the ambient near-IR radiation.**<br></blockquote><div><br></div><div>The peak wavelength for a human body</div><div>thermal spectrum is 10 microns - in the so </div><div>called long-wave infrared range. You shine </div>
<div>if you're standing out in the snow, but the </div><div>human body is not really very hot. About </div><div>the same as your house interior, which is </div><div>that temperature, by design. So you don't</div>
<div>stand out much.</div><div><br></div><div>See <a href="http://en.wikipedia.org/wiki/Infrared">http://en.wikipedia.org/wiki/Infrared</a></div><div><br></div><div> -- Bob</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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