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Mailing List Logs for ShadowRN

Message no. 1
From: Marty <s457033@*******.GU.EDU.AU>
Subject: Thermo vision and stuff (from calvin)
Date: Fri, 18 Oct 1996 20:29:54 +1000
> On another topic, has anybody seriously considered the rules governing
> thermographic vision. I mean that if the movie 'Predator' is anything to
> go upon, thermographic vision is not just a vision enhancement.
Depends on whether you have to operate in the visual spectrum at the same
time. If you're just collecting thermographic visual signals, then you
can give a false-colour map depending either on the wavelength or the
intensity of the observed radiation.

If you're trying to use normal vision at the same time, then it gets a
little bit more tricky, because you still have to see the other natural
colours, and a false colour overlay would be confusing. If you're trying
to see normal and thermo at the same time, the heat emisions would look a
bit like a pale red tinge around or coming from hot objects.

It'd be interesting to speculate if Thermo-sensitve eyes could see the
violet region of the spectrum, and what other colours would actually
'look' like it they could.

> It seems that the vision has not much in the way of depth perception. It
> is also difficult to distinguish cool objects from one another. Doesn't
> this mean that the person would be tripping over objects the person can't
> see and/or can't judge the distance from.
Yep.... the best fight in SR that I ever saw involved a fight in a jungle
at night, while it was raining. The temp was exactly body temperature, so
thermo weas useless; Couldn't distinguish the heat sources from the
background. Lot's of blindfire/freindly fire opportunities.... Smartguns
don't work if you can't ID the target.

I'm not sure about the depth perception. I find it hard to judge the
distance of any source of light.

> I've spoken to people in the army who have used night-vision goggles, and
> the fact that there is no depth-perception is apparently hazardous and
> disorientating, forcing people to have exaggerated gaits.
Yup; Apparently it was one of the major contributing factors to the
blackhawk incident we had a while ago. If you exaggerate you walk, what
do you think it does to your ability to fly?? The army loses more
aircraft that way *grin*.

> Another point is stealth. Isn't it alot more difficult to hide with cammo
> from a guy with thermo vision? How do thieves and assassin types get
> around without being seen then? Is there some sort of cammo which
> prevents thermo from spotting anything?
Yes indeedly.... you are a source of IR radiation, which kind of makes it
equivalent to trying to sneak around with a torch on.

Invisibility spells do not work agaisnt thermo radiation, again because you
are a source of the 'light' which the spell would normally act against.
Either way the spell works.... (see the previous debate) you either overheat
if it absorbs the radiation, or it can't scatter or bend an emitted beam.

Some possible methods exist to avoid thermo detection; Wear ice packs or
some kind of cooling body suit equivalent to a refrigerator... The
concept was mentioned in the novel 2XS (from memory).

Or, do what we did, and wait for a really big, cold rain storm to come up,
which makes the thermo sensors useless. The water hitting you and running
off you cools your surface temp down so much, and absrobs so much IR
radiation that you blend in to the surroundings a whole lot better.

Anyone else got any ideas??


Further Reading

If you enjoyed reading about Thermo vision and stuff (from calvin), you may also be interested in:


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