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cryptoknight
At least invisibility doesn't work with tech... but Improved bends light around people... and affects tech... so you use Ultrasonic Vision to see them... so they cast silence...

I'm resorting to pressure plates and trip lines to create a facility defense to catch invisibles...

Speaking of that... can suppressive fire stretch it's 10m from close to far instead of from side to side?
Ol' Scratch
Simple, old-tech security measures are the best. You know, things like, say, doors.
Crusher Bob
Magical security
Patrolling spirits, hellhounds and other critters w/ astral perception can all spot the invisible guy

Physical access control:
Doors don't open by themselves, elevators don't move by themselves.

Mundane animals:
Guard dogs can smell the invisible guy
hyzmarca
Sprinklers. Invisible people still obey the basic laws of physics, including two pieces of matter cannot occupy the same space at the same time. Water will not fall through him but will, instead, cascade off of his body, producing an obvious outline.
Crusher Bob
For the more exotic security measures: micro-thin feeler wires that descend out of the ceiling when the building in unoccupied. Invisible guy brushes the wires, security knows where he is.

If you think SR tech is up to it, the feeler wires can be sensitive enough to detect minute air displacements, meaning that he doesn't even have to touch them. Of course, this means you can't be running the AC at the same time...

cx2
Also remember that instead of silence simply making him invisible to ultrasound it in effect makes a "black hole", at least as I imagine it. The sound won't bounce off the guy using silence, but equally it won't be bouncing off any walls behind him or the ground near his feet so you get this area where the ultrasound simply registers nothing at all.

Note that this would be my interpretation through common sense. To me I imagine it being like there being a big black hole where the terrain should be, rather than it bending sound around the target.
kzt
There are a huge number of security sensor systems out there. The spiffy new version is FOUO, but the 1997 version of Perimeter Security Sensor Technologies Handbook is really great at suggesting approaches that the casual GM will NEVER think of.

The other obvious approach is the use of floor-to-ceiling turnstiles that block the corridor and require an ID check of some sort to unlock so they can turn. And the camera system watching this will correlate the turnstile turning and nobody in the field of view and sound an alarm.
Hank
Somewheres in BBB it talks about capacitive fencing, which wouldn't care about invisibility or silence. It just goes off whenever material is nearby. I think it's in running the shadows.
FriendoftheDork
I'm not even sure Improved Invis will work against passive IR detectors. I mean, the body still produces heat, and when moving the temperature of the room will change rapidly. Light bending around the person will prevent animals and cameras from actually seeing him, but PIR should still work.

OR do you disagree?

DTFarstar
I forget if it does fool IR as well or not, but even if it does that doesn't mean room temp won't change. You could get a general area from that.

Chris
Crusher Bob
Improved invisibilty works against the thermographic vision of trolls and various other critters, so infrared cameras and beams are out.
hyzmarca
Improved Invisibility works against thermal sight. It does not work against any other thermal sense, however. IR cameras, it would fool. Simple heat detectors, it would not.
Sir_Psycho
There is a lot of useful security measures in 2nd and 3rd edition books such as Corporate Security Handbook, the Keeping the Rabble Out chapter of State Of The Art: 2063, The Neo-Anarchists Guide To Real Life has a section also, as does the unofficial sourcebook Paranoid Animals of North America (yes, that's Shadowrunners, kids).

Finding some of them in hardcover will be difficult and expensive if not outright impossible. But i'm sure you'll manage it quite easily looking for e-books.
Critias
QUOTE (Crusher Bob)
For the more exotic security measures: micro-thin feeler wires that descend out of the ceiling when the building in unoccupied. Invisible guy brushes the wires, security knows where he is.

If you think SR tech is up to it, the feeler wires can be sensitive enough to detect minute air displacements, meaning that he doesn't even have to touch them. Of course, this means you can't be running the AC at the same time...

If you make them monofilament wires (of the super-sharp magically cutty Shadowrun variety), this would work even better. You could just look for the falling now-visible body parts, spurts of blood, and listen for the screams!
Riley37
QUOTE (Crusher Bob)
If you think SR tech is up to it, the feeler wires can be sensitive enough to detect minute air displacements

Ripley: What does it key on?
Ash: Micro changes in air density.
Ripley: Micro changes in air density, my ass.



("Alien", 1979, for you young'uns what don't know those lines.)
cryptoknight
Ok... I was trying to think of things that a typical shadow dweller might have (basically a guy who is cutting in on Tamanous' territory and they've hired the shadowrunners to put him out of business permanently. I figure he has a doss of some sort for processing of inventory and would have suitable defenses for that.

So the dangly wires are out, but the sprinklers are good... and after reading all of your ideas, I was also thinking a vibration detector that feeds into the area's AR and puts a humanoid shape (scaled for size based on the intensity of the vibration) over places where it detects vibrations but active sensors don't pick anything up.
Critias
Or you could just have an inch or sand poured on the floors throughout the building.
DireRadiant
All you need is one Watcher.
The Jopp
QUOTE (Critias)
You could just look for the falling now-visible body parts, spurts of blood, and listen for the screams!

The parts would actually be visible as they are now a separate object from the targets aura, as would the trail of blood.
DireRadiant
Chem sniffers been mentioned yet?
Hank
QUOTE (hyzmarca)
Improved Invisibility works against thermal sight. It does not work against any other thermal sense, however. IR cameras, it would fool. Simple heat detectors, it would not.

Ok, we're getting a bit sciency to explain game mechanics here, but here's the deal. IR/heat sensors all sense the same thing...electromagnetic fields radiating away from a warm thing, be it a white-hot poker or a warm body. (Our eyes aren't sensitive to typical temperature wavelengths, fortunately.)

Heat you feel diffuses, but most "heat detectors" are really sensitive to the light. Look for "Blackbody radiation" on wikipedia for a full, mind-numbing explanation. Diffusion is much too slow to make a practical detector.

But, if you want to tell your players that a "heat detector" would bypass invisibility, I'm pretty sure you'd get over on them. You might argue that invisibility has a limited wavelength bandwidth.

Or you could tell them to shut up before an anvil falls on their head.
Tarantula
Hank, just to be contrary, there are thermosense organs similar to pit vipers available as bioware that DO bypass invisibility. Then again, theres no sensor of them.

Also, if the mage throws in levitate (or is a mystic adept w/traceless walk) then the vibration sensor is out too.

Radar sense neatly still works though.
Buster
Improved Invisibility + Stealth + Physical Mask + Levitate = defeats all possible mundane detection except radar (and ultrasound and thermal sense knows something is there, just no pinpoint location). One watcher defeats all spells.
Tarantula
And improved masking with a grade of 4 (to be able to encompass all the spells) masking them to be hidden, and then the regular masking to mask your own aura to look mundane, the watcher might just get confused at the flying mundane.
Hank
QUOTE (Tarantula)
Hank, just to be contrary, there are thermosense organs similar to pit vipers available as bioware that DO bypass invisibility.

You know, I was going to argue with you that Pit Vipers must be sensing IR photons rather than temperature changes, but I just did a little Google-fu, and, from the paper I just read, it looks like researchers are concluding that they actually sense temperature changes, not IR photons. The jury's still out, but it looks like people who research this agree with you.

I personally would have expected that there's too much variation in ambient air to detect the small temperature shift from somebody standing in a room, but it looks like that's not true, at least not for the Pit Viper. So, yeah, Pit Vipers (or some technology derivative of that) don't sense IR, it's actually heat. And they wouldn't be fooled by invisibility.

Ok. Enough friggin' science.

EDIT: You know, I don't have Augmentation memorized, but one might think that Pit-Viper sensors would be available as bioware. It occurs in nature and it has a market...it seems like somebody would be growing/farming pit-viper sensors and selling them.
Ol' Scratch
The guy you quoted just told you they exist. And they existed in previous editions, too.
X-Kalibur
QUOTE (Doctor Funkenstein)
Simple, old-tech security measures are the best. You know, things like, say, doors.

I concur.
Hank
Ah, yes. He did.
Lagomorph
I'm suprized no one said this yet, since they're great against spell stealth.

Wards.

And since watchers (by the rules are only ever force 1) they get 2 dice for perception (force + skill), if you add a half decent infiltration skill they can't see you either.
Tarantula
Also, I did note that there is no technological equivalent of thermosense organs.
Adarael
Listen, if a PC wants to buy and cast (and sustain or have sustained for him) Improved Invisibility + Silence + Levitate, plus get two levels of initiation devoted to being sneaky, AND have a high enough infiltration to bypass things like beings seen by astral mages and watches... I'm gonna let him be pretty freaking sneaky and not get seen or detected by much of anything.

Expecting that the above PC can be detected by certain unassailable security measures is like being confused when the troll adept who has Smashing Blow + Strength 12 + Unarmed Combat 7 + the knowledge skill "Structural Engineering" is only mildly inconvenienced by things like walls, and can wreck a car by punching it.

That's what the character is built to do.
Tarantula
The best part about it, is even with all those tricks, a radar sensor in the middle of the base can see for 100m, and pinpoint mr quiet floating mage no problem.
Adarael
Hence why I said "Much of anything". There's always something.
Sunday_Gamer
I feel the need to preface all my posts with "Not yet fully versed in SR4" however...

The many different things that used to cause me and my improved invisibilitied ass problems:

Astral Security, that includes, watchers, dual creatures, wards all that good stuff. Yes you CAN get masking high enough to cloak both yourself and your invisibility spell but then you have to use the astral landscape to hide and sneak around so really. just because a spirit/astral guardian doesn't see you as a mage or you're spell up doesn't mean it won't stop you. These things are intelligent, they might actually KNOW who works on the premises, who's allowed, what security wears, who's in charge... plenty of room for mischief there.

Ultrasonic vision... nasty stuff that. Any security device that operates on similar parameters, motions sensors, ultrasonic hearing...that kind of stuff.

Physical security, tightly controlled doors and elevators.

Disturb ready surfaces, sand, sensor wires, water... let's see what else...
Tarantula
Watchers are worthless. Cloaking yourself is a fantastic thing. Especially since then you aren't shining brilliantly on the astral, and thus can hide easier. (Less worry about non-astral people, as they invisibility spell takes care of that.)

Ultrasonic vision is pretty hampered by silence/sound barrier.

Doors and elevators are the biggest problem, thats where thinking outside the box is useful.

Disturb ready surfaces are nice, but levitate fixes most of those.
KarmaInferno
QUOTE (Hank @ Nov 16 2007, 03:59 PM)
Ok, we're getting a bit sciency to explain game mechanics here, but here's the deal. IR/heat sensors all sense the same thing...electromagnetic fields radiating away from a warm thing, be it a white-hot poker or a warm body. (Our eyes aren't sensitive to typical temperature wavelengths, fortunately.)

Just a nitpick, but you meant "radiation", not "electromagnetic fields", right?

They're not the same thing.

smile.gif

Personally, I like hallways full of invisible masked monowire whips, that only stop thrashing about if someone with the right aura/ID widget/whatever enters.



-karma
kzt
Wards. Use an alarm ward behind a regular ward, so as to keep out pesky spirits who might casually set it off. Putting a force 8 ward in an elevator shaft would be kind of cool also. I don't think the invisibility spell will make the test vs 16 dice of ward.

The other clever thing about a ward is that spotting it forces the mage to be astrally perceiving, which is easily noticeable by spirits and such and is kind of unusual. It would seem likely that a bound spirit would quickly know and recognized the auras of the few astrally active people in a facility.
Moon-Hawk
QUOTE (kzt)
Use an alarm ward behind a regular ward, so as to keep out pesky spirits who might casually set it off.

No nested wards.
Tarantula
Masking again lets the mage appear not to be astral while astrally perceiving. It also lets him impersonate the aura of the ward creator, and waltz on through (provided he takes the proper time/prep/spells to do so).
kzt
QUOTE (Tarantula)
Masking again lets the mage appear not to be astral while astrally perceiving. It also lets him impersonate the aura of the ward creator, and waltz on through (provided he takes the proper time/prep/spells to do so).

When you use astral perception you become a dual natured creature. You can't hide that. You can disguise it as something else using masking.

"To disguise her astral form to look like a spirit or other
astrally active creature, the character must be capable of
astral projection."

"Anything active on the astral plane has a tangible astral
form—projecting magicians, spirits, dual-natured beings, and
so on. Astral forms are more colorful and brighter than auras, as
they are astrally “real.?"

And to synchronize you have to track the ward creator astrally, while seeing the ward. So, there you are, outside the door to the ZYX top secret research facility, and you go off to track the guy who created the force 10 ward. Who's probably at work in the security firm that employs him, along with the rest of the initiated security mages. You'll just sneak through their wards and find his office while hoping that nobody notices your astral form? While leaving your inert body in the doorway?
hyzmarca
QUOTE (Hank @ Nov 16 2007, 10:59 AM)
QUOTE (hyzmarca @ Nov 16 2007, 02:11 AM)
Improved Invisibility works against thermal sight. It does not work against any other thermal sense, however.  IR cameras, it would fool. Simple heat detectors, it would not.

Ok, we're getting a bit sciency to explain game mechanics here, but here's the deal. IR/heat sensors all sense the same thing...electromagnetic fields radiating away from a warm thing, be it a white-hot poker or a warm body. (Our eyes aren't sensitive to typical temperature wavelengths, fortunately.)

Heat you feel diffuses, but most "heat detectors" are really sensitive to the light. Look for "Blackbody radiation" on wikipedia for a full, mind-numbing explanation. Diffusion is much too slow to make a practical detector.

But, if you want to tell your players that a "heat detector" would bypass invisibility, I'm pretty sure you'd get over on them. You might argue that invisibility has a limited wavelength bandwidth.

Or you could tell them to shut up before an anvil falls on their head.

They may sense the same thing, but they don't sense it in the same way. IR cameras and thermographic vision see. They take the IR radiation and use it to build a visual image of whatever. Sensors don't see, they don't build visual images, they just sense. You can't download a photograph of an intruder from an IR sensor, though you could from an IR camera.

Invisibility is based around sight as a metaphysical concept. It fools sight. It doesn't fool other senses, including other senses that sense the same sorts of radiation. Because heat sensing is fundamentally different from sight in a metaphysical way, it can see through invisibility.

By the same token, a visible light sensor wouldn't be effected by II unless it was a visual sensor such as an eye or a camera.


Also, radar works.
Tarantula
First, "(provided he takes the proper time/prep/spells to do so).". That'd be, before you're at the door, while you're in the legrunning stage. Find the name of whoever set up the ward via hacker, then find out he likes to go boozing after work, slip in, assense him, and bam, you have your key.

As far as the astral perception goes, masking lets you get around it. SR4, 190, "A character who learns masking can change the appearance of her aura/astral form to do the following: look mundane,"

If you are perceiving, but mask to make yourself look mundane, then you look mundane, even though you are entirely active on the astral plane.
kzt
QUOTE (Tarantula)
If you are perceiving, but mask to make yourself look mundane, then you look mundane, even though you are entirely active on the astral plane.

No, you are an astral form that looks like it's not a dual natured creature. That's like disguising your boat in the middle of the ocean to look like a barn. It may be a really convincing disguise, but most people are still going to be kind of suspicious.
X-Kalibur
QUOTE (kzt)
QUOTE (Tarantula @ Nov 16 2007, 01:45 PM)
If you are perceiving, but mask to make yourself look mundane, then you look mundane, even though you are entirely active on the astral plane.

No, you are an astral form that looks like it's not a dual natured creature. That's like disguising your boat in the middle of the ocean to look like a barn. It may be a really convincing disguise, but most people are still going to be kind of suspicious.

An amusing analogy to be sure. The fact remains that you aren't visible on whatever technological sensors there are, yet you manage to be a mundane looking aura... yeah, thats gonna raise some suspicion really quickly.
HappyDaze
It should be possible to make a spell that allows you to step through a (closed) door or even a section of wall. It doesn't break the 'rules of magic' as set forth in Street Magic. As a Sustained Manipulation spell, you could render a touched object immaterial with no visable chage to allow passage through. It might be best to limit it to Touch range and base the maximum hardness effected on hits. I'd have this make the object immaterial NOT the person, otherwise you have too many other uses for the spell.

This could be done even while invisible to bypass doorways.

Hank
QUOTE (KarmaInferno)
Just a nitpick, but you meant "radiation", not "electromagnetic fields", right?

They're not the same thing.

Radiation is a broad category. It's anything that travels in straight lines away from an object, including nuclear particles and electromagnetic waves.

I assume you thought I meant nuclear radiation, but I meant electromagnetic radiation. Two things come off a hot object: 1) Heat energy that you can feel (travelling like perfume travels in a room, by diffusion) and 2) Infrared radiation (aka light from the electrons wiggling around randomly). Since [2] travels in straight lines and at the speed of light, it is useful for imaging.

But, yeah, I meant radiation. Just not the kind you're thinking of.

@Hyzmarca, I'm pretty sure that IR sensors use radiation as well, but, since they don't need an image, they don't bother with all of the optics required to actually create a picture. It makes the sensors cheaper.

EDIT: Oh, I see what you're saying...it's focused images that Invisibility works against, but it doesn't stop passive detection.

Here's a good example of why this is a waste of time...we're talking about a game. Science should be applied sparingly, if ever. You're right; if radar works, invisibility doesn't bend all light around you, but then the criteria becomes "does the sensor have proper optics for imaging?" So things break down there. But I AM excited to be able to flex my nerdy muscles.
Paradigm
I'm curious, since the improved invisibility spell more or less bends light, would a sort of laser system that, instead of a single constant beam, shoots out a hundred beams or so a second and then measures the time delay between between 'transmission' and reception not be an excellent tripwire to detect invisible intruders. I.E. An invisible mage walks through the tripwire, the light gets bent around him and thus takes about 20% longer to reach the receptor on the other side. Tripwire system detects the anomylous delay, sounds a silent alarm to summon guards.

I'm quite sure I've heard of a system like this before, as I highly doubt I'm making it up on the spot. But since we know the speed of light, can measure time in basically millionths of a second and could very easily calibrate something that'd measure the time it took a beam to go from one part of the hallway to the other, isn't this an excellent (theoretical) detection tool?
Hank
QUOTE (Paradigm)
An invisible mage walks through the tripwire, the light gets bent around him and thus takes about 20% longer to reach the receptor on the other side.

Yeah, that would work assuming that the magic doesn't take care of the time delay, but I think we've looked WAY too far behind the curtain here. I know that I, as a player, would be pissed if my GM pulled this stunt, even though I know it should work.
Paradigm
Oh, this would never be something I'd use as standard, but in a high security run I'd definately do it. I'd not implement it without some warnings to the PCs though. (as in shadowland/shadowsea/jackpoint mention, something the decker'd fish up while researching the security measures. A KE security manual that got leaked, or whatever). It's the sort of thing one might run into at a secret corp research site, not just any office. It'd have to be built into the wall, for one, integrated with the design of the building and it's security system. It'd be spoofable, provided the decker can break into the node, etc.

I don't go out of my way to screw players, but tactics using a few standard and commonly available/known spells like that should never be infallible. If a runner can get a hold of it, you can be sure that any AAA or AA knows of it's existance and has been looking at countermeasures.

Edit: There's also always the inert magic detection clouds, I forgot what they were called. Perhaps someone remembers off the top of their head?
Falconer
I'd say for simplicities sake... improved invis bends all light from UV down to longwave IR (heat vision). Which means no nonsense bout pit vipers seeing through it. If they're looking for infra-red improved invis blocks it.

If anything... the authors aren't consistent (or don't bloody understand Infrared is infared... it doesn't matter if you stick an infrared camera at it, or an infrared intensity detector... Do you get an image out of the device or number saying how intense the infrared is inthis direction? (also those alarm systems are based on infrared as well... pyroclastic infrared sensors are at the heart of a lot of them).
Wavelengths on radio are too far, so it has no effect on radar and the like. (really radar in augmentation is rediculously good. Use it... and if it's being jammed... it's almost as good of an alarm

Wavelengths on radio are too far, so it has no effect on radar and the like. (really radar in augmentation is rediculously good. Use it... and if it's being jammed... it's almost as good of an alarm


I'd have more respect if the sensors actually picked up say the spectral lines of the hot CO2 constantly produced by living critters. That's another idea for an interesting sensor... one which scans the room for concentrations of CO2, almost guaranteed to be from exhalations. One thing those crazies in the environmental lobby don't tell you is that the mean free path of a photon in CO2's is measured in feet... so it's possible to measure concentrations w/ some kind of LIDAR system.

If it really bothers you that much, you might be able pick up some kind of 'heat shimmer' like a mirage in the area of a mage in the case of a poorly cast ImpInvis w/ some special image processing software on the camera. (say if mage casts it and splits up his dice pool to multiple targets, or casts it while maintaining other spells). In which case, a special camera might pick if there's not enough successess on the spellcasting test. Just suggesting as a house rule if it helps.

Or how about, nanotech... dust everyone who comes in w/ some kind of nanite w/ a very small tracking transmitter that only transmits when it can 'steal' power from the bodies natural bio-electric fields (I utterly hate that explanation... your body doesn't produce that much... I'd rather some well they activate the genes that make electric eels electric, so you generate electricity from sugar/oxygen in your blood directly). Instead of tracking the people... track 'activated' nannites.
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