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unless the description specifies how far the thermal vision is, asume its as far as any other optic systems. Example, if a PA has telescopic sight 4000 feet and thermal vision, then the thermal vision is also 4000 feet (like a filter added over the telescopic sight).

IRL the "night vision" used by today's US forces (generation 6 i think) combines thermal optics, passive nightvision (light amplification), and UV vision (UV lasers replace visible targeting lasers). The system combines the inputs to make one super clear image. That's why US soldiers can see their targets and shoot accurately in near total darkness.

Just wondering how far can heat sensor reach? The argument is that person A is saying you need to be close to register heat and Person B is saying that Samas have optic systems that can detect heat signature from a distance.

Which person is right? what distance do you guys use?

heat sensors aren't as cut and dried as the stats imply. you can see heat as far as you can get good LoS. the big thing on range is the size of the signature and the resolution.

the farther away the heat source is, the smaller and 'fuzzier' the image is. (just like regular light ) the closer it is, the more detail you can see. for example, a persons extremities tend to have a slightly lower temp than their torso. so at close range, a persons arms and legs will be look slightly darker in the thermal vision. at farther distances these distinctions will blur away and you might only see a human shaped blob at roughly human body temp. at even further distances you might not see the shape at all, just a brighter point on the screen.

for example, a robot is stated in rifts with a 4000 foot thermal vision mode. that would mean that it can see heat sources clearly out to 4000ft. it would be able to see details like major facial features and such. it might be able to ID a human or vehicle out ot a mile, but would not be able to tell much more than genral type. so it could tell you there is a human in a feild, but you could not tell if it was say, your freind Major Tom. out to a few miles you'd only be seeing a bright point, and would only be able to make a distinction between large and small, animals or vehicles.

Situation: My master vampire is in her lair and when the PC's enter, she knocks over a bunch of oil lamps in a domino effect, spilling oil and fire everywhere. The room goes up in an inferno with lots of black greasy smoke that has no real place to vent.

What are the effects on thermal and infra-red in a situation like that?

it would swamp the gadget. thermal sights are designed for a specific range of IR frequencies (heat). in a room filled with fire and hot smoke you wouldn't be able to see very far. the room would be a bright blur. objects like humans or anything not on fire might show up as darker shapes against that background. but you'd only be able to see about as far as you could without the thermal vision.

thermal vision doesn't really allow you to see farther, just see a spectrum of light that you normally can't.

A basic heat sensor is just a bi-metallic strip that bends with the temperature. Something like that needs to be close so part of the question you have to ask is how much sophistication (ie cost) went into this system?

TheDarkSaint wrote:What about IR sensors? Would the heat or smoke affect them?

same as with Thermal.

thermal sights are just IR sights set to 'see' a specific range of IR frequencies.

the different is mostly in processing. an 'IR' sight makes an image based on signal strength (often based on the scatter of IR light from an IR lightsource), while thermal is a passive IR system that translates the signal strength into 'temperature' values to make the image.


the reason the thermal sights are so popular with the military is that the IR lightsources of the old IR 'nightvision' sights show up like beacons to all sides, and as thernmal is a passive system, it's 'stealthy', making it easier ot go unnoticed.