Hi guys,

I had a currious situation happen this past Monday's game session. During this game I played a Banshee who tried to scout out a building (outside the building) while in Mist Form. Now, the building had Ultrasound Sensors, and I ended up in a minor discussion with the GM about what would actually happen in this situation.

Here's my question for you:

Would an Ultrasound Sensor be able to register a character in Mist Form?

The way I see it, ultrasound is sound, and sound is basically moving airmolecules, and a sensor works by detecting the reflected sound. Personally I wouldn't expect the Mist of the Mist Form to cause any form of reflection of the ultrasound. My GM's reasoning was that he believe that the Mist would cause a minute and localized distortion in the ultrasound, which the sensor system would be able to pick up. What's your oppinion? Or is there a rule concerning this somewhere in the books, which we have missed?

(For the record, the GM decided that the sensors could potentially detect the character in mist form, provided that he rolled well enough for the system, and I rolled poor enough for the Infiltration roll.)


/Kyrel

I would say that just like Radar and Sonar can't pick up clouds and Fog that the Ultrasound sensor can not detect you in mist form. Although a Thermographic sensor would.

Why, is the Mist warm?

I think the GM is right, about one thing: there are minute distortions in the air. The problem is that there always are, from currents, convection, etc. It's just useless noise.

One would think that advanced scanning systems would do something like the Kinect, where an infrared dot pattern is projected over the secured area and an IR camera looks for changes in the dot pattern. This alongside a standard camera.

This should show up even invisible or gaseous intruders to some degree, as the dot field should distort slightly even from those things, enough that a computer should be able to detect.

Or even have a painted IR grid pattern across the area that the IR camera watches, that would get blocked by an intruder crossing in front of it.



-k

Perhaps, but that sensor doesn't exist in SR4. (Try the Laser Monitoring System, though… for non-Mist, non-Invis targets.)

On the question of ultrasound, though, it works by bouncing pulses off hard things.

The mist is probably not warm but it would most likely have a different temperature then the ground or the area near by.

Why? Why not, say, exactly the same temperature as the air it's in? Or a noisy, meaninglessly different set of temperatures, just like normal ambient air?

I think a more pertinent question would be - how easily could a security system identify a localised patch of mist as a security threat? If there are metahuman eyes at the other end then he might have a small chance of noticing something was wrong by the oddly deliberate path of the mist (circling the building) but an automatic system would likely have no chance as the alarm parameters would have to be so vague that it would be dragging the spider out of bed ten times a night.

Err i'm pretty sure Radar can pick up clouds, it's not my area of expertise but isn't a lot of modern weather forcasting based on radar picking up clouds of gas.

Final thought: It's your GM's own fault for letting you play a banshee but it seems like the GM has the right of it. There's a chance that the sensors would pick you up.

All but the most sensitive of security systems won't detect gasses such as mist, because if they did they would generate false positives all day.

Remember folks it's 2070+ the system might be smart enough to analyze and disregard false positives. Anyone saying "Surely the system isn't capable of that" needs to be reminded you can get full 5 sense VR from your phone direct into your brain THROUGH YOUR SKULL and that there are creatures that can turn into clouds of mist in the world.

And yet, it strains belief to *assume* that these sensors and systems could detect… mist. If they were specifically tuned for it, *maybe*. Just use a camera.

A security system does not necessarily have to have a binary alarm, either off or on. It could kick anomalous readings up to security for verification.

For high security areas yes it would mean false positives quite often, but the guard on duty can just glance at the monitor with the blinking light, to see what's got the sensors confused. It's not like the facility needs to go into full alert lockdown every time the camera hiccups.

And my comment on the projected IR pattern sensor, well, yes, it isn't in the rules, but it's the kind of sensor that SHOULD exist by 2070, considering we can make them today. A patch of mist might be quite obvious if you're shining a light beam through it's space.



-k

As I said, there *is* that. It's the Static Laser Monitoring system. We're talking about ultrasound, which shooting pulses through mist would not notice at all.

I'm just saying that a camera (tiny, cheap) can see mist, so there's no reason to give extra abilities to ultrasound. It is already the king of sensors.

I have trouble believing an ultrasound would reflect enough sound to give an accurate reading off mist. I'm no expert but it seems a system sensitive enough to notice a mist form would be useless in fog (like Seattle has every day) because it would constantly be reflected off of water vapor.

I'd say that only the most paranoid security systems would notice this.. most systems would just disregard it as some random breeze. But a paranoid system might think it's the beginning of a gas attack, and therefore respond to it.

I think the solution to this is pretty simple.

Use the Ultrasound vision modifiers for Light or Heavy smoke, as appropriate, depending on how fat the mist forming banshee is.

I believe its -2

See, and that's way too minor. That reflects the fact that ultrasound sees *right through* smoke.

However the situation the OP put fforth is he decided to turn into a gas cloud and scout around a building. Provided there wasn't other fog going on a single discrete gas cloud floating around the premises might very well get marked by the security agents for special scrutiny. It could indicate a drone under ruthinium poly, a air spirit or a banshee using their mist power, it's both within the level of tech for the game and within a certain level of predictability to take notice of such things.

Bottom line, no single power, spell, or piece of gear should guarantee complete safety or completely bypass the need for any kind of skill check.

It's not invisible (AFAIK), so any person or camera will see it. What it *is* is silent and intangible, so radar, sonar, ultrasound, etc. do nothing. *That* it hardly a crazy gamebreaking state of affairs.

I'd invert that, personally. As you said, ultrasound sensors take a -1 for light mist and a -2 penalty for heavy mist. To my mind those small penalties to see through mist mean that it is largely invisible to ultrasound sensors. Since the largest visibility penalty on the table--representing near-complete obscurity--is -6, I'd apply a -5 penalty to perceive light mist and a -5 penalty to perceive heavy mist themselves (rather than to see through them). This penalty would stack with other visibility modifiers, as appropriate, including modifiers for environmental mist. I don't know whether I'd say Mist Form is light mist or heavy mist.

I just woke up, but I hope my reasoning is fairly clear.

this. The guy might see you, but he'd see a fuzzy lookin' misty area, not necessarily be like "OH MAN VAMPIRE"


Ruthinium Poly protects against Ultrasound? I thought it was light-only?

Mist Form wouldn't provide complete safety, anyone with astral sight or any sort of magical security at all would notice it immediately. So, security mage/spirits, that bacteria that glows around active magic (mist form power being activated would count IMO) or a security Hellhound to name a few options.

Also, not sure what professional level we're lookin at in this hypothetical, but only a well trained guard or one who is experienced with magic would think that a patch of mist might be a banshee or an air spirit. Most would just be like "huh, that's weird" and then continue their patrol, in my opinion. Unless of course they're highly trained, but if they're highly trained they're probably well-equipped and they probably have some way of determining for sure if that's magic mist or just a weird patch of mist.

I heard something before that sums up security situations like this nicely, please note I'm paraphrasing, I'm not sure if this comes from a book or a dumpshocker.

In the 6th world efficiency takes priority over security, and the bottom line takes priority over safety.

Unless you're dealing with a super high security set up, they likely don't configure their system to notice something as minor as a mist form because dealing with false positives costs time and money, not just to pay the guards, but all the time lost when employees have to go into lockdown.

From the comment I thik he meant by visual obeservation - seeing (with eyes or cam) a patch of mist that behaves in a way it shouldn't.

Now as far as detecting the the mist with ultrasound or radar, that's probably doable, but it would take two things :
* a very sensitive sensor - the mist has very little in the way of rader or sound absorbption, which means the perturbation is minute
* an analysis software package that's configured for it.

Note that such a system is likely to create quite a lot of false positive as it will probably be tripped by natural mist, maybe even wind and other air movements.

The odds for something sneaking around in a mist form are rather minute, I don't think many security systems will be configured that way. Of course if what you're doing onsite is likely to attract magic-oriented troubles, the odds gets higher.

Mist form doesn't bypass anything really. If you have a hermetically sealed door, the character is stuck. If you look at things realistically, how often do vampires go running against corporations? You are talking about 1% of 1 in 100,000 people. Vampires are narcissists that are more interested in stocking their heard of cattle, and sending their minions to do their work. There would still need to be a stealth check, yet if you are worried about this. mist form is seen on the astral, so why not use your watchers? Every bypass method has some vulnerability. Even if gateway or teleports were allowed, a detect magic spell will trigger and send an alert.

A drone with ruthenium is still going to trip ultrasound, laser trips, and doorways. Mist form doesn't do anything more than invisibility and silence accomplishes. A move through earth spell would effectively accomplish the same thing, and should be allowed.

EDIT: Rats..., Hound and others beat me to this. Bummer I left it open and sitting.

Why do you force the game world to be stupid? Dealing with "false piositives" costs the same amount of money having existing security resources in place does, your already paying them, they are already there, so it doesn't cost anymore money.

I can say this having done both military and private security, management doesn't give a damn about things that cost security time, that's what their paying them for. It's a lot more costly to repair a breach then it is to have security jumpoing at shadows, or in this case clouds of mist.

People can dumb down opposition down to a three your old level if they wish but there isn't anything directly supporting that assumption. Quite the opposite in fact, anything worth paying runners to break into likely runs in the moderate to good security range.

That's assuming the sensors can detect *mist* in the first place. Ultrasound can't. Use a camera.

Or better yet, use a spirit/elemental. Problem solved. Couple that with the fact that you will want magic security anyhow.