I think the answer is YES it still emits light, but from the wrong end.
The invis spell would "bend" the light that way.

What do you see when you see a person?

Light from an external light source reflecting off their body. The invisibility spell edits the light coming from a person's body. In the case off thermographic "light" the body is generating it on its own. In order for an invisible flashlight to work the spell would have to be able to distinguish between the light being reflected off the invisible person's body ( or thermographic light being generated by the individual's body heat ) and the light being generated by the flashlight. I don't think it would. It would require the spell to have intelligence. The spell would need to know which light the invisible object wishes to generate and which light it doesn't.

Note : The light would have to editted after it reflects off the person's body ( instead of editting it before it reaches the person's body ) As preventing light from reaching the invisible person's body would render them quite blind.

Another reason for the invisible flashlight not to work would be as follows: A ray of light is generated by an invisible flashlight. Now the ray of light hits either a person's eye or a hidden security camera or a wall. Under the theory that you'd be able to see the light reflecting off the surroundings but not from the flashlight itself it would have to work as follows: If it hits the wall then the invisibility spell chooses not to edit it. But if it hits the guard's eye or a hidden security camera the invisibility spell does edit it. Once again this results in the invisibility spell gaining "intelligence". The spell is choosing which light to edit based off external information it probably wouldn't know.

So my answer is no. The invisible flashlight would not generate light.

or just have the light be edited when it hits the observers lense or eye.

that way a flashlight can generate light for the holder, but maybe not for the observer

by the very fact that the sensor accepts photons as input

the magic just ride the beam of light in and then mess around when it hits something that reacts to light and altering the signal there.

basicly, it edits the person out of the image. just like what happend to some people in soviet russia

to much detail can at times be a bad thing
do one have to explain at a quantum physics level why a magical spell is able to damage a person?

I take it this sort of thing counts as shoehorning major changes?

Meh. I think it was a slight mistake for them to write down that it bends light... on the other hand... perhaps part of the spell is a minor clairvoyance effect... or some crap like that. XD

Its a game with magic... therefore it never has to make total sense... only mimic it.

they say it warps light. ok so warping is a kind of bending, but it does not have to say it warps it around the subject. it may well be the writers way of saying that it mess up the light somhow else. "a warped interpetation of reality"

Okey-dokey. I think I have it, or very nearly. The spell says that it "warps" light. Light is a wave (yes, yes, and a particle too, shut up Heisenberg), and warping it could mean not simply refracting the light (re-directing it) but increasing or decreasing its wavelength.

Suppose I have some visible light just floating along when suddenly the light hits this mysterious field (the spell) and goes "Woah! I feel like really excited, I'm being charged with super mana energy and I'm vibrating so fast I'm an X-Raaaaay!!!"

In it's super hgh-energy state it quite naturally passes through the character, wall, whatever but as it leaves the field (spell) it's energy drops back to where it was before ("Man, that was a buzz, but now I'm blue again"). Voilá - invisibility.

Now how can we resolve this in terms of different people seeing different things? Okay, here goes! In the below, M equals our invisible Mage and A and B are observers. My dinky little ascii arrows are the paths of light going through the mage.

invisibility and similar have allways been presented as a kind of indirect illusion. rather then aiming right at someone that should directly experience the illusion, you aim at something that will appear alterd based on the spell.

in many ways its similar to the armor spell. it puts a layer of magic over the target of the spell, and this layer helps stop anything harmfull at the size of a bullet or larger.

if one was to follow the extension of the LOS requirement that some try to use on the invisibility spell, then the caster would have to see each and every bullet fired at the person coverd by the armor spell. if the caster didnt see a bullet then the armor spell didnt work on said bullet.

so the LOS requirement for the invisibility spell is only for the initial casting. the caster have to see where he wants to target the spell.

This needn't be listened to, and certainly isn't needed for the explanation I outlined, but the FanPro FAQ states that improved invisibility can be used to establish LOS. I don't know how much people consider that official, but it's there in black and white pixels. Just thought I'd mention it.

Anyway, the description of the spell does say "warps light" so I'd go with LOS allowed if only for that. If you can cast a spell round a corner with fibre-optic goggles, then quite frankly warping light by magic is good enough for me. Anyway, if the players don't think of this tactic, then I'm certainly going to surprise them with an NPC using it.

where is this faq posted?
if its in german i dont care about it...

err, thats for SR3 not SR4. so its hardly applyable in this case...

and even then is a year old

btw, having the spell require a force higher then half the OR of the item target is flat out wrong. its the observer that need to resist the spell, not the object or person coverd by the spell...

Yeah, well, to be frank most of us here consider the FAQ to be a piece of junk. The writers don't even pretend that their answers have anything to do with the actual rules; much of what's in there directly contradicts what's written in the books, but without claiming to be errata so it's impossible to figure out whether to follow the actual rules or their "FAQ".

knasser's idea, while interesting, is a logistical nightmare. Let's look back at this diagram, and expand it a little so we can name points on M's body:

heh, thats why its magic. magic fixes the flaws

i dont know, is there any book that talks about magic moving at anything less then the speed of light?

The FAQ lets you kill a main battle tank with a derringer firing standard ammo.

Think about that for a second.

The FAQ lets you kill a main battle tank with a derringer firing standard ammo.

This, friends, is why we ignore the parts of the FAQ we don't like. It isn't canon untill its canonized. The FAQ is not yet available in book form.

must point out that converting all light to gamma radiation would not cause cancer. It would cause complete organ failure within a few hours even with only a few minutes of exposure.

Okay then, counterpoints:

1) The argument wasn't so much that the difference is meaningful, but that there is a difference at all. What this does is force the mage to either a) see into the future and know exactly where the target will be, and adjust where the altered rays will be sent accordingly, b) alter the rays in a swath around the observer, albeit a small one, to compensate for possible movement, or c) introduce artifacts into the invisability projection which will be easily discernable to the human eye *or* a well-written analytical program.

2) The computational intelligence point wasn't the actual argument here, though that is an interesting area to explore. The argument here was that it is physically impossible in a great many cases to make M invisible to A without also making him at least partly invisible to B and C, both of whom are supposed to have resisted the spell. To C the mage would be almost completely invisible, and to B he will be partly translucent. In some rare cases where two observers are looking at the mage at the exact same angle even if one of the observers resists the spell the mage will still be invisible, because the spell is busy making M invisible to the failing observer.

3) Point dropped, though page 57 actually has more to do with simulating the effect of several people rolling the same test several times, and not with simulating how much more difficult and in this case mana-intensive it is to affect multiple people at once.

4) So the retina is specifically exempted from the effect of the spell, or the effect is specifically damped by the presence of a retina? I'll buy that, though it's adding even more conditional clauses to the body of the spell.

5) *shrug* Okay.

6) Covered flashlight abuse. Still unanswered.

6b) In fact, this doesn't really answer the OP's question of an invisible flashlight either, does it? Of course, neither does my interpretation. so

7) Radiation: see hyzmarca's post above.


Oh, and your solution also doesn't deal with the shadow problem that I'm still wrestling with in my interpretation either.

Why does it need to see into the future exactly? Isn't the Astral the ultimate Unified Field Theories allowing for effective faster than light travel? At least for informational purposes.

As for the D20 boards on WOTC, go look at some of the larger threads. There are debates every bit as vehement as this (often moreso) about things like whether a 'Hulking Hurler' can throw a moon sized piece of adamantine or not, including refering to whether he'd simply sink into the ground or even if that much adamantine would be dense enough and crush itself enough to become a singularity.

SR4 for all its fantastical elements is a game far more grounded in reality (No wish spell just for starters) so the arguments about it will tend to be a little bit more gritty (and nitty for that matter).

To Concord Flight attendant; "But, if we are flying faster than the speed of sound how come I can hear you?"

I would say that A flashlight in a invisibility field does emit light.
Does the light exit said field? For ease of game mechanics say YES.

Now give people extra die to roll vs the spell if they notice the flashlight beam comming from empty air, expecially in fog or smoke.

But the answer is very important. It influances the flavor of the entire magic system.

The sr3 FAQ says imp invis establishes LOS????????!!!!!!!!????????


The rules for what magic can and cant do in MITS clearly stated magic can never be used to establish LOS.

Knasser. The main advantage of my theory over yours is that I don’t need to know how it works (note that your theory has been torn apart and mine hasn’t). The only thing I disobeyed from the RAW was a small bit of flavor text witch contradicts the need for a resistance roll. It also has it workings linked to other physical illusions.

Physical invisibility doesn’t mean it has to physically affect light. It can refer to the fact that it affects physical cameras.

Having the spell affect every object (living or not) with the conceptual quality of seeing within LOS of the invisible object (you can’t see it if your not within LOS of it) works at least as well, and means other physical illusions can work in the same way,

It also more really explains the relevance of object resistance and the absence of the higher drain true invisibility which doesn’t bother with the energy saving system and thus denies the relevance of OR and resistance rolls.

hyzmarca “But the answer is very important. It influances the flavor of the entire magic system”

you only need to know what magic dose, not how it dose it, especially in a world where the characters don’t know how it is done and there is a distinct possibility that different casters develop the same spell effect in different ways. Remember that the rules specifically do not say weather totem spirits really exist.

Edward


Ps. If you want to fix the radiation issue then shunt the light energy in a different direction. Have it translate into ultra low frequency radio.

I've updated and tried to clarify my views on improved or physical invisibility. In short I view physical immunity as a manipulation of light as it that is reflected off of or generated by an invisible object or person. It does not go around and identify each and every person or device which is looking at the invisible object or person so can it can maipulate the light when it reaches their eyes or viewing devices.


Physical ( or Improved ) Invisibility House Rules
------------------------------------

House Rule #1:
---------------------
Physical Invisibility dissapates all spectrums of light ( including visual and thremographic ) being reflected off of or generated by an object or person. The spell cannot tell the difference between thermographic light and the light from a flashlight. Thus an invisible flashlight would not work. In effect when it comes to light generated by the invisible object or target the spell is the visual equivalent to a silence spell.

Note: There are limits to what the physical invisibility spell can cover up. For example a low force invisibility spell may not be able to handle stopping the thermographic light from a blowtorch or the effects of an invisible flash grenade. Stronger invisibility spells are obviously able to cover up more.

House Rule #2:
-----------------------
The second function of Improved Invisibility is that it replicates all light that hits the invisible object or person on the opposite side of the person as if the light had traveled through unimpeded. The light must be allowed to hit the invisible person or he would be rendered quite blind. So any effects from the light hitting the target beyond visual ( such as a damaging laser ) is still felt by the invisible object or person. The laser light would still be replicated on the other side of the target but it would be an illusion equivalent of the original light and carry none of the effects beyond visual of the original light.

Note: All physical illusion spells work by modifying or negating existing light. ( with the obvious exception of illusions of things that generate light. Like on illusion of a fire ) For example, a runner mage is being followed some guards and sneaks into a completely dark room. He casts the illusion of a dragon to startle the guards. When the guards enter the room they can't see the dragon because there is no light. But when one of the guards turns on the lights then the light from the ceiling reaches the illusion spell and is modified to reflect outwards to show the dragon.

House Rule #3:
-------------------------
Improved Invisibility is a physical illusion and like all physical illusions resisting it does not cause the illusion to "go away". Instead the result would be that resisting individual is able to see that the illusion is fake. They may be able to see an outline or some visual disruption that signfies where the invisible object is. Such nuances are generally beyond the capabilities of most technological devices. However a spectral analyzer or similar device may be able to detect a physically invisible individual.

Note : It's generally cheaper for the corp the go for other methods of detecting invisible characters such as ultrasound or ( a personal favorite of mine ) pressure plates on the floor.

House Rule #4:
-----------------------
Improved Invisibility cannot be used to establish LOS. You cannot establish LOS with an illusion spell. If invisibility is cast on a wall, then you see an illusion image of what is on the other side of the wall. But this is light produced by the invisibility spell and not the original light that was reflected off the whatever was on the other side of the wall. A magician unaware of the invisible object may not be able to immediately ascertain why he or she can't establish LOS.


Other Methods of Physical Invisibility
-------------------------------

Illusionary environment
-------------------------------
It is also possible to pull of a physical illusion of the surrounding environment. For example if a magician "overlays" an empty hallway with the illusion of an empty hallway then any number of runners can travel down the hallway sight unseen. ( And probably unheard too as most physical illusions modify both sight and sound. ) The disadvantage of course is that this sort of illusion isn't that portable and would affect anyone who wandered into that hallway runner or guard.

Transparency spell
----------------------------
It is also possible to pull off invisibility with some sort of transparency spell. But that's not even remotely an illusion spell. That's a pure physical manipulation spell. It's an open question to whether an individual would be able to see with transparent eyes.

Radar Invisibility
--------------------------
Since illusion spells can generate sound as well as light it stands to reason that it should be possible to design a type of sound invisibility that allows for ultrasound or sonar or radar waves to hit the object or person to be deadened when the are reflected and then replicated on the other side of the individual. I imagine the drain for such a spell would be the same as visual invisibility. Furthermore a magician could design a spell that handled both sound and light. But the drain for that spell would be oppressive.

to truely mess with your minds:

would a mirror created with a illusion be usable for targeting around corners?

Check out "On The Run" adventure, page 19, under "Detecting Invisibility." It doesn't address some of the "bend light" discussion, but it might help your group come to a decision on handling invis.

Personally, we just suspend our disbelief and say the invis character can see, and can't be seen (though can be found via other senses, leaves trail on dusty floor and so on). We don't much care how this happens any more than how trolls and dragons are around. It just is.

Woah! This thread is getting long and complicated!

My two pence...

Trying to create an invisible source of light is bloody silly, just as a stealth plane or submarine using active sensors (sonar or radar) will reveal its position.

For comedy value, consider the mage walking through a dark room shouting "Ping!" and listening for echoes.

I would allow invisibility to be cast on an object to permit line of sight for indirect spells, but not direct spells. Of course this does render the mage casting the spell visible to his target. This isn't a problem when it's a mook, but the caster would themselves be vulnerable to indirect spells cast at them.

Just a few comments:

First I have to say: ~HAHA~
Second I have to say: ~HAHA~ again.

Why? Pretty simple: You guys are now experiencing the same problems that german players and GMs had with SR3 due to a fucked up translation that said that physical indirect illusions physically bend light around its primary target despite the illusionary effect for an observing "target" (Note that in SR3 both the person that was made invisible and any observers were "targets" of the spell).
But it wasn't a purely german problem back then, because more than once (even on this board) in the discussions on how the physical version of the invis spell worked the light bending theory came up .. soon to be followed by problems of being blind, potential overheating and a dilemma with spell resistance.
The RAW-solution back then still imposed certain LOS issues like the example given with the invisible troll working as shield for another person (the real trouble starting once that second person suddenly steps into vision field of a person that couldn't see her just seconds before).

So what's new? Someone in the SR4 staff brought that light bending into the spell description of physical invis ... and the argument starts once more.
And currently of two solutions one (namely the one where light is bent / warped at / around the observer) pretty much does what the SR3 version did, leaving certain LOS problems and the other solution (affecting the light at the invisible person) still raises the question how that would allow for a resistance test (the described effect being more of a complete physical alteration that a manipulation spell usually imposes).

But why the second laughter? Because of the FAQ-reference ... Even before shadowrunfaq took over the job, there were certain rulings in the FAQ that had nothing to do with RAW (and to a certain extend raised the question if Rob Boyle had actually read his own rules, since at some point he did the FAQ himself). Once shadowrunfaq took over we got a dedicated FAQ writer ... who simply created various instances where he went more or less straight against RAW and game concept... The LOS creation through walls by the physical invis spell being one of them, because the illusion of seeing through a wall (even if you decide to actually show what truely is behind that wall) doesn't generate what is required for casting spells: actually seeing a target with either physical or astral sight.
And that FAQ answer still ignores the debate whether or not in SR3 an invis spell can actually be cast on a single non-living object.

So what's my solution?
I'll stick with what I've played in SR3 and that's the solution where light is altered at / within a perceivers "eye" to create the false image of "there's nothing there" and where even the person under invis spell has to resist the spell in order to see him / herself. Both leading to the following when it comes to flash lights: The light of carried flash light will be "invisible" to anyone who failed to resist the spell ...

And since somebody brought up the "magic isn't intelligent" issue:
Magic clearly is "intelligent" despite what stood in MitS (or even prior rulebooks), since it's capable of fulfilling the desired purpose of spells with target restrictions.
But magic isn't intelligent enough to make decissions outside that. A spell cannot alter it's purpose or willingly ignore a normally valid target. But it will ignore any target that isn't valid by design.
To make an example: You could create invis a physical manipulation where light actually is bent around a target (let's just ignore the fact that this person would be blind during that time and let's also ignore the potential heat problem *that IIRC would only arise after quite a while*) => Such a spell could not be resisted by any observer since the target of the spell is just the light that's being bent. Now let's assume that our invisible person is holding a flash light and turns it on (doesn't matter that she can't even see the light) ... In this case the light (or better its reflections) of the flash light could be perfectly seen by any observer and only that part that actually travels back to the invisible person would be subject to the light beinding effect of the spell.