Oh, I understand. The original question<div>was what Cyberguys level gadgets could</div><div>do in terms of seeing bad wiring inside a</div><div>wall.</div><div><br></div><div>If cost is no object, one can of course </div>
<div>do more. A lot more.</div><div><br></div><div>Devices operating in the 1THz range</div><div>can see people inside their house.</div><div>Through walls. There were discussions</div><div>about the legal implications of all this</div>
<div>several years ago.</div><div><br></div><div> -- Bob</div><div><br></div><br><div class="gmail_quote">On Thu, Jan 28, 2010 at 9:04 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;"><div class="im">On 1/28/2010 8:48 PM, Bob Kline wrote:<br>
> How cool was the room?<br>
<br>
</div>Thermostat is normally 72F, but that's in another room. I'm in the room<br>
with the servers, which is usually about five higher.<br>
<div class="im"><br>
><br>
> You seen to have a short sleve<br>
> shirt on, but I think I can see the<br>
> back of a chair, walls in the the<br>
> background. Is it a big room?<br>
<br>
</div>I wear short-sleeves year-round, primarily because of the higher<br>
temperatures in the vicinity of my workstation. That was actually taken<br>
in Dec of 2007, I think. (The date is off on Flickr, but that's because<br>
the source is a BMP, and the timestamp was screwed up due to a few<br>
workstation migrations.)<br>
<br>
Room is about 750 ft^2, or about 6000ft^3.<br>
<div class="im"><br>
><br>
> Jet gets to the fact that because<br>
> you stand out some the room might<br>
> be large, and-or cool<br>
<br>
</div>I don't think you understand how far-IR temperature monitoring works.<br>
If you'd like, I can delve into a discussion of microbolometers and<br>
measurement adjustments stemming from surface emissivity, ambient<br>
temperature and ambient humidity values.<br>
<br>
There's more at work than just the wavelength of quanta, there's also<br>
intensity of emissions, considerations of atmospheric absorption and<br>
considerations of ambient temperatures reflecting off of other surfaces.<br>
<br>
What it boils down to is that in practical conditions, I can (and do,<br>
for use cases such as those that that software was written for) measure<br>
surface temperatures to within 0.01C.<br>
<br>
Don't forget I also control the palettization -- the conversion of raw<br>
temperature numbers to RGB pixels, which goes towards making differences<br>
"stand out."<br>
<div class="im"><br>
><br>
> -- Bob<br>
><br>
><br>
> On Thu, Jan 28, 2010 at 8:18 PM, Michael Mol <<a href="mailto:mikemol@gmail.com">mikemol@gmail.com</a><br>
</div><div class="im">> <mailto:<a href="mailto:mikemol@gmail.com">mikemol@gmail.com</a>>> wrote:<br>
><br>
> On Thu, Jan 28, 2010 at 8:02 PM, Bob Kline <<a href="mailto:bob.kline@gmail.com">bob.kline@gmail.com</a><br>
</div><div class="im">> <mailto:<a href="mailto:bob.kline@gmail.com">bob.kline@gmail.com</a>>> wrote:<br>
> > On Thu, Jan 28, 2010 at 6:03 PM, Michael Mol <<a href="mailto:mikemol@gmail.com">mikemol@gmail.com</a><br>
</div><div class="im">> <mailto:<a href="mailto:mikemol@gmail.com">mikemol@gmail.com</a>>> wrote:<br>
> >><br>
> >><br>
> >> The chief problem with "darkvision" as it applies to passive<br>
> near-IR is<br>
> >> that there is a lot of ambient near-IR radiation that's not<br>
> 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>
> ><br>
> > The peak wavelength for a human body<br>
> > thermal spectrum is 10 microns - in the so<br>
> > called long-wave infrared range. You shine<br>
> > if you're standing out in the snow, but the<br>
> > human body is not really very hot. About<br>
> > the same as your house interior, which is<br>
> > that temperature, by design. So you don't<br>
> > stand out much.<br>
> > See <a href="http://en.wikipedia.org/wiki/Infrared" target="_blank">http://en.wikipedia.org/wiki/Infrared</a><br>
> > -- Bob<br>
><br>
> <a href="http://www.flickr.com/photos/28208534@N07/3681419505/in/set-72157620862996406/" target="_blank">http://www.flickr.com/photos/28208534@N07/3681419505/in/set-72157620862996406/</a><br>
><br>
> I don't?<br>
><br>
> What kind of image is this? i.e., how<br>
> is it corrected?<br>
><br>
><br>
><br>
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</blockquote></div><br>