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Nightshade-
Ok, I have two question.

I have a guy in my group that swears and insists that thermographic vision can see through walls and pick up the heat given off by something in a room well beyond the interior wall. Put simply he claims that if he is using thermo while walking through a hallway, and he looks at a wall he can see through it and pick up the heat from a troll that is 10ft or more into the room. Is there anything in the rules that says that is possible? Are there any thermo imagers in the real world that can do that?

I've heard that trolls and dwarves see in normal vision and thermo vision at the same time. I've heard that's the way it's done in some novels as well as it is discussed in the 2nd Ed. book Cybertechnology. The reference that says that states it is in the discussions in the book IIRC. Not sure what IIRC means. Does anyone know what area or page says that? Or is there anywhere else in any rulebooks that it states that and what page please?
mfb
no to both questions. the guy is either insane, or he's confusing thermo vision with mm-wave radar. different materials are transparent to light from different parts of the spectrum. thermo vision, in SR, basically allows your eyes to see into the near infrared. very few building materials are transparent in the near infrared--including glass; you can't see through windows if you're only using thermo vision. many building materials, however, are transparent to millimeter wave light--but there are no rules for mm-wave vision.
SL James
... yet.

As for the meta vision, that should be in the SR3 rule book. is on p.49 of M&M. They are active all the time.
The Stainless Steel Rat
QUOTE (Nightshade-)
Not sure what IIRC means.

If I Recall/Remember Correctly
Dog
The see-through-walls idea is often based on one particular scene in the movie Robocop. I don't think that it's ever actually referred to as thermographic, but the hero looks through a wall and sees that colorful red-people-on-blue-background effect that we laypeople imagine as thermo imaging.

By the way, I've heard about fire-fighters using some kind of portable imaging device to locate people in burning buildings. Anyone know how that works?
Serbitar
You can only see hot immovable objects through a wall.
But it is possible to see humans through curtains and such if the stay there for some minutes, but not if they are fast mooving.
SL James
Firefighters use an infrared thermographic camera that can differentiate between objects of different temperatures so that they can see people who need to be rescued or hot spots that need to be contained while not being blinded by the smoke.
Dog
To penetrate smoke, not walls. Got it.

If I can be picky for a moment, Serbitar, it sounds like what you're describing is that one would see the heat transferred from a hot object onto a chunk of wall. In that case, you'd have to take into consideration the heat conductivity, etc. of the barrier itself.
SL James
Indeed, you would.
Serbitar
QUOTE (Dog)
To penetrate smoke, not walls. Got it.

If I can be picky for a moment, Serbitar, it sounds like what you're describing is that one would see the heat transferred from a hot object onto a chunk of wall. In that case, you'd have to take into consideration the heat conductivity, etc. of the barrier itself.

Yes, thats exactly how it works.
Crusher Bob
In the US, most interior walls are sheets of sheet-rock seperated by air. This means that any heat something leaning against one side of the wall transferred to the wall would be diffused by the air spacing in the wall as well.
KarmaInferno
QUOTE (Dog @ Jul 31 2006, 09:18 AM)
The see-through-walls idea is often based on one particular scene in the movie Robocop.  I don't think that it's ever actually referred to as thermographic, but the hero looks through a wall and sees that colorful red-people-on-blue-background effect that we laypeople imagine as thermo imaging.

Amusingly, they acheived the "thermographic" look by not actually using any sort of heat-camera, but by dressing all the actors in spandex that had been painted in the vivid colors, and then fuzzing it a bit with camera effects.


Apparantly at the time renting an actual thermographic camera was too expensive, especially for one brief scene in the movie.

QUOTE
In the US, most interior walls are sheets of sheet-rock seperated by air. This means that any heat something leaning against one side of the wall transferred to the wall would be diffused by the air spacing in the wall as well.


Gypsum wallboard is in and of itself a pretty good heat insulator as well.


-karma
Butterblume
It is theoretically possibly to see someone using thermografic vision through a wall, if the circumstances are right. Most are mentioned already, the target didn't move around much, the walls are good heat conductors (stone is, wood isn't, for example). The temperature of the building and your surroundings is a factor, etc.

Basically it's just easier to disallow this at all smile.gif.
Findar
Actually the scene I think of is from the Seals movie where the sniper sees the guys behind a brick wall and shoots them through the wall with his Barret sniper rifle.
SL James
"Ooooh, Navy SEALs!"

Yeah... No.
mfb
heh, at least it's not U.S. SEALs.

regardless. i'm not going to say that there isn't a scope that does what Paxton's scope does in that movie, but if there is, it's not an infrared (ie, thermographic) scope.
Frag-o Delux
I want the railgun and scope in Eraser.
SL James
QUOTE (Frag-o Delux)
I want the railgun and scope in Eraser.

God sees your crimes.
Oracle
But he/she/it doesn't tell anyone.
mfb
he tells me. that's how i know who to kill.
Cray74
QUOTE (Dog)
By the way, I've heard about fire-fighters using some kind of portable imaging device to locate people in burning buildings.  Anyone know how that works?

As noted, it's to see through smoke.

The traditional firefighter method of finding people in a burning house is to get down on hands and knees and sweep with your hands because the smoke will fill the room to the floor.

http://qconline.com/progress2003/prog_dspl...3;id!143552

http://www.bullard.com/thermalimager/Train..._overview.shtml

As for seeing through walls, that would depend on heat from a heat source (like a body) warming the nearside of the wall. As you can see in the link above, IR is useful for finding hotspots hiding in walls - but they *have* warmed the nearside of the wall.

The average interior wall - drywall/air gap/drywall - is a pretty good insulator, and is opaque to IR light. A body would have to warm the far side of the wall so it glowed in IR, then radiate that IR across the air space, which in turn would need to warm the next wall before the thermographic camera could see it. So, I wouldn't bet on it.

Interestingly, glass also tends to be opaque to IR, though mirrors still work.

This website has many, many thermographic pictures...at the bottom. The top has a lot of cameras. A lot of the photos seem to be repeats, but it should give you a nice idea of how thermographic imaging works.

http://www.ir55.com/infrared_IR_camera.html
mfb
god says you can live, Cray.
Critias
For now.
SL James
I like the tricks sp... Milholland wrote about in SOTA63 (Keeping the Rabble Out) about using IR reflective paint to ambush people coming around corners who don't have thermographic vision.
Dewar
QUOTE (One of those articles)
A couple of years ago, a group of Moline firefighters wearing only their socks walked across the cold station floor and then out of range of their new thermal camera.

When they gathered later around the machine, it displayed their footprints. The camera detects heat, so hot feet on the cold floor left tracks invisible to the human eye.


Do you guys really think they all had to strip down naked to do this test? Homoerotic much?
PBTHHHHT
Some things are best left unknown. Though I guess it'll be a great plot for some gay porn movie. Again, something I wish not to know or dwell upon. nyahnyah.gif

edit: And no, they were meaning that the firefighters were not wearing boots so their body heat could easily be transferred from their feet (and socks) to the floor.
Grinder
We don't who did watch the test? Some female scientists maybe?
PBTHHHHT
Now now, try and remember that there's audience of not just females out there who wouldn't mind watching this sort of thing.
Shrike30
Hey, most girls I know think firefighters are hot.

Besides, there's some female firefighters... nyahnyah.gif
SL James
But the vast majority don't look like Diane Farr, or even come close.
HullBreach
Ive had a little bit of expeirience with Infra-red (Simalar to thermo, think the black and white FLIR footage you see on those police chase shows) weapon sights courtesy of uncle sam, so I'll chime in a little.

IR sights do operate on the principal of infra-red radiation, which is basically light outside the human visual range that is associated with heat. Now 90% of using one of these things effectively is a basic understanding of how radiant heat behaves, as well as knowing what IR light will and won't pass through. Some examples:

You can see through most fabrics very easily, but it does haze up the details a bit. I remember being able to clearly make out people moving inside a tent from over a mile away, though their light discipline was excellent and I couldn't even make them out on NVG's.

Foiliage is also pretty ineffective at blocking light in this spectrum. Tree trunks will, but bushes and other greenery barely even break it up. I remember being able to tell where one dude had just finished taking a leak before heading back to his fighting hole because I could still see the hot piss running down the tree trunk. Pretty wild.

Depending on the sensitivity/sophistication of the unit (I've handled both 'grunt proof' simple models as well as one scientific insturment grade model) you can aslo tweak the settings to 'acclimatize' its settings to function better in your enviroment. We had one tuned so finely, we could tell you which troops were using their MRE's heater tabs while eating their dinner in their fighting holes (they release some hot vapors when activated).

Now thermo is about 10 steps more complicated, requires more training to use, but it is also a hell of a lot more capable. A well tuned IR unit lets you see hot or cold. A well tuned Thermographic unit lets you see HOW hot or cold a thing is. In game terms, this could be pretty useful in a variety of situations. Folks using thyroid boosters and certain other high-performance bioware will either have higher body tempatures or distinct hot-spots associated with the gear. The footprints on the floor scenario metioned earlier is also possible with this level of gear.

Also note that disturbed earth is easy to spot using this, as the newly exposed earth will generally be cooler. Aircraft can actually spot some heavy vehicle tracks hours after the fact from the warm tracks caused by the intense ground-pressure of their passing.

As for the walls scenario, it comes down to construction materials and insulation, but a player whose been leaning against a wall for 10 minutes will be visible on the other side dead-air space or no, simply due to the radiant nature of heat.

Spent shell casings are very visible in both IR or thermo (I think they're a little easier to spot in the black-and-white IR displays though), as are hot gun barrels. The hot gasses associated with firing tend to dissapate very quickly.

Finally, some chemical compounds that are inherantly unstable (high explosives, particularly cheap soviet bloc ones) are usually slightly warmer than ambient tempature due to the fact that they are essentially decaying.

The important thing to remember here is that its all about contrast. A 98deg F human body in the snow, or even a nice 74deg F office building is easy to spot. They are also easy to spot in a 110deg F metalworks. But stick them in a 98-ish degree F jungle, and they will blend in fairly well.

Also take into account shapes. The part of our brain that processes images is pretty well tuned to spotting people. But once we start to break up their shape a little bit, it gets tougher. Israeli infantry wear lumpy misshaper helmet shrouds for this reason, it breaks up the head-and-shoulders profile most troops insticntually look for (mostly cause thats how our targets are shaped). Simply mottleing and breaking up ones IR pattern with some enhanced camoflage (the new cammies used by the Marines and Army utilize material that does this) goes a long way to hiding ones self.

This is why Thermal/IR systems are used to supplement other systems, as without tons and tons of field usage, they just arent that insinctual to use.
Fix-it
I'm guessing this was RECENT equipment Hullbreach?

as in, a year or two?
what generation are they on for NVGs anyway?

I got to play with a pair of 1st gen (god they were bulky)

and 3rd gen (better but still fuzzy) night vision goggles, and I couldn't see to well with 'em...
IR sounds like fun. too bad it's restricted tech we civilian pukes won't get for another few years. and then have to pay an arm leg and left eye for.
HullBreach
These are actually availible to the public:

http://elcan.phpinternet.com/www/SPECTER_0_0_Index.htm

But they cost like 12k last time I checked. Hell, I can't even afford regular range time lately, so somthing like thats a wish for if I hit the lotto!

While I was in we were using Gen 3 NV gear, which has gotten much better. Supposedly the next gen stuff will be almost as sharp as normal vision due to some new manufacturing process for the intensifier tubes (which I've always felt were the weak link, give me an IR enhanced CCD instead!).

The thermo and IR stuff was mostly demonstration samples I just happened to be in the right place at the right time to handle. The IR weaponsights are probobly going to be GI issue for crewserve weapons in the near future, so thats good news as it will drive the public prices down some.
KarmaInferno
QUOTE (HullBreach)
But stick them in a 98-ish degree F jungle, and they will blend in fairly well.

This is one of the things that always bugged me about the Predator movies. Both made mention of sweltering heat in the upper 90s range, and this is the environment the Predators preferred.

Wouldn't that make their human prey more or less invisible to their thermo vision?


-karma
Moon-Hawk
Well that's what makes the hunt challenging, what with humans being so squisky and weak. smile.gif
SL James
Please don't tell me you're trying to apply science to an action movie.
Fix-it
yeah, you really shouldn't bother with a movie that features an average guy shooting a minigun from the hip.
KarmaInferno
Jesse Ventura is not an average guy!

He's Jesse Ventura!

You take that back!


-karma
LilithTaveril
/me sets Jesse Ventura on fire.
Smokeskin
AFAIK full recoil force from a 5.56 minigun is around 500 newton, or around the effect gravity exerts on 100 pounds. Braced against the hip, a strong guy should be able to handle that.
RunnerPaul
QUOTE (Fix-it)
yeah, you really shouldn't bother with a movie that features an average guy shooting a minigun from the hip.

has produced two US State Govenors.

There. Fixed that for you.

cyber.gif
Austere Emancipator
It was an M134, so a 7.62mm minigun. Even then, though, at 2000rpm, perhaps even 3000rpm, a big guy would be able to handle the recoil, to an extent -- I don't know about the other peripheral problems of firing such a weapon unmounted. But he certainly wouldn't be able to lug around the 200+lbs of gun, batteries and ammo, assuming he's to fire it for more than 30 seconds.
SL James
True, but to be fair Blain fired it in short, controlled bursts. It was Mac who went apeshit and let the thing fire until it ran out of ammo.
HullBreach
Ahem.....the mini-gun thing has been well documented as impossible here:

http://world.guns.ru/machine/minigun-e.htm

Scroll down, its towards the bottom. These guys know there shit, I trust what they say.
Austere Emancipator
They make the mistake of assuming that the gun would be set to fire at 6000rpm. The most recent M134 models fire at 3000rpm, the ones from when Predator was filmed mostly fired at either 2000rpm or 4000rpm. At 2000rpm, we're only talking about a bit over twice the recoil of an M240 -- and according to The Gun Zone, the RoF on the Predator M134 "was reduced to 1700 rpm in order to reduce torque and to lower the voltage required to power the motor that rotates the barrels." They're absolutely right about the weight issues, though, and I have no idea how an M134 ejects empties.
Smokeskin
Imo the guys who wrote that at guns.ru have very little idea of what sort of force a human can brace themselves against. Even the 120 kg recoil from an M134 shouldn't knock a strong man over if he was properly braced for it.

If they reduced the cyclic rate, then it becomes much more managable. I've fired 7.62 NATO ammo from a 11 kg LMG at 1200 rpm from a standing position, hanging at the hip but with no hip-brace, without a problem. At 1700 rpm, with a heavier weapon and the centripetal stabilation effect from the rotation barrels, recoil would be even less. If you added a hipbrace, I should think you could easily go double that.
HullBreach
QUOTE (Smokeskin)
If they reduced the cyclic rate, then it becomes much more managable. I've fired 7.62 NATO ammo from a 11 kg LMG at 1200 rpm from a standing position, hanging at the hip but with no hip-brace, without a problem. At 1700 rpm, with a heavier weapon and the centripetal stabilation effect from the rotation barrels, recoil would be even less. If you added a hipbrace, I should think you could easily go double that.

You actually unintentionally make a good point here:

If a normal machinegun is capable of reliably operating in the 2000 RPM range of rates of fire, why complicate things with a minigun?

The interesting and under-noticed point the www.world.guns.ru guys make is the power consumption of such weapons, which is enourmous! Unless you want to haull a cartload of batteries around with you, these weapons really aren't feasible.

The other operating force thats at play here is the gyroscopic forces caused by the rotating barrels. Though hard to quantify, these would be significant due ot the high mass of the barrel cluster.
HullBreach
QUOTE (Smokeskin)
Imo the guys who wrote that at guns.ru have very little idea of what sort of force a human can brace themselves against. Even the 120 kg recoil from an M134 shouldn't knock a strong man over if he was properly braced for it.


120kg of peak recoil energy is about 264lbs of straight-line force directed back at the user. While this could be resisted, not even the strongest unenhanced user could maintain a semblance of accurate fire dealing with that.
Austere Emancipator
QUOTE (HullBreach)
If a normal machinegun is capable of reliably operating in the 2000 RPM range of rates of fire, why complicate things with a minigun?

An interesting theoretical question, but kinda pointless because no normal machinegun (in the kinds of calibers we're talking about here) is. 1200rpm is at the highest end, and while an M134 can keep 2000rpm up all day an MG3 can only be worked at 1200rpm will be seriously damaged if you go cyclic for very long (a minute or more).

That doesn't make a MANPAD minigun anything other than pointless, though.
HullBreach
A valid point, I got my number confused for a few moments there (I just woke up, still absorbing cafffine).

On a semi-related note, the US Military (I've only seen the Army do it so far) has began using M-134's on top of Hum-Vees. This is kind of an interesting development, as it really provides a crazy level of firepower to respond to an ambush with.

Personally I've always liked the MK-19.
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