Difference between Ultraviolet Perception and Nightvision?

[Gaelinic]

Can someone explain the difference between Ultraviolet Perception and Nightvision in terms of their game effects? They both cost the same points and seem to provide similar effects. However, for the same point cost, it seems that Nightvision is a better ability since it allows you to see in dark buildings, sewers, and caves. Ultraviolet Perception would seem to indicate that you need some source of UV light to still see.

I'm just wondering why you would purchase one over the other. Thanks.

[Barton]

UV needs a source. In Vietnam rotting vegetation was the source of the UV for early night vision goggles. So in a completely dark room a character with UV perception would not see anything at all.

[Deejmeister]

UV vision needs a source of UV light. Night Vision only works in natural darkness rather than the power Darkness (it only offsets vision penalties to PER roll and therefore does not work in situations were you would not get a PER roll).

[Ternaugh]

Can someone explain the difference between Ultraviolet Perception and Nightvision in terms of their game effects? They both cost the same points and seem to provide similar effects. However, for the same point cost, it seems that Nightvision is a better ability since it allows you to see in dark buildings, sewers, and caves. Ultraviolet Perception would seem to indicate that you need some source of UV light to still see.

I'm just wondering why you would purchase one over the other. Thanks.

Because UV goggles may not be appropriate in a Fantasy Hero campaign. ;)

By Nightvision, I am assuming that we are talking about a light-intensifier. There has to be some light( there's some, even in "total" darkness), it's just heightened so that the image looks like "daylight". Of course, that means that a bright light source will become blindingly bright. So, you could temporarily disorient a character using Nightvision, if you exposed him to a bright light. UV vision wouldn't necessarily be affected in this way, but you need a source of UV light to see.

Of course, YMMV,
JoeG

[Hawksmoor]

UV vision needs a source of UV light. Night Vision only works in natural darkness rather than the power Darkness (it only offsets vision penalties to PER roll and therefore does not work in situations were you would not get a PER roll).


Ding Ding Ding!!!

We have a winner!!!

Each has it's benefits and Drawbacks and thus costs out to be about the same. IMO *all*enhanced senses are overpriced for utility (don't get me started about wierd builds like Rapid Sight :rollseyes:), but regardless the powers work exactly as described by Deejmeister.

Hawksmooor

[Dust Raven]

The difference is subtle.

Nightvision: Need not be thought of as it's own sense, but just a modifier that eliminates the penalties for darkness with normal vision. It can allow for color vision in any lighting condition, including total darkness. Some GMs may choose to limit the color vision by the amount of actual visible light available however (total darkness would be black and white, while twilight would still be relatively full color).

Ultraviolet Perception: Is a specific sense. When attached to the Sight Group, it allows one to see into the UV part of the spectrum (normally invisible to normal humans). Other than being able to see in the dark (with available UV light), you can see a number of marvelous things that are only visible in UV. Flowers and many insects have different pattern in UV, some clothing looks different (like under a blacklight, which is really just intense UV light) and in a superhero/high tech world, there are invisible things that can only be seen in UV, alarms using UV beams of light for sensors, covert communications using beams of UV light, etc. Also, if you are affected by a Sense Affecting Power that only affects your Normal Sight, you still have your UV Sight.

[Susano]

UV vision needs a source of UV light. Night Vision only works in natural darkness rather than the power Darkness (it only offsets vision penalties to PER roll and therefore does not work in situations were you would not get a PER roll).

I'll need to remember this. Thanks for the clarification.

[David Blue]

I use infrared for things like pit-viper heat-sense, nightsight for equivalents to the big eyes of nocturnal animals, and ultraviolet vision for underwater heroes.

[PhilFleischmann]

I've always had a problem with the way Nightvision is built. IIRC, it is simply +4 Vision, Only to offset penalties from darkness (the natural condition, not the Power Darkness).

If this is all it takes, then someone with plain old +4 really good vision sees in the dark as well as a person with base vision sees in the day.

Is it really only -4 for darkness? Does that mean with stars and moon or with no light at all like in a cave underground or in a closed dark room? If I spend the 5 points (CMIIW) for Nightvision, can I get up in the middle of the night and confidently walk to the bathroom and use the toilet without missing or tripping or stubbing my toe? Even if it isn't in a house I'm familiar with or if the furniture has been rearranged? Can I pick up a glass of milk off a table in a dark room without spilling it? Can I read a book in a dark room? I think it's a stretch to say that a mere +4 gives the equivalent of daylight vision in the total absense of light.

It seems to me that the ability to see in total darkness needs some other construct besides a bonus versus a penalty to a PER roll. What is needed is a way to say the caharacter gets a PER roll even when he normally wouldn't. (OT: The same thing applies to N-Ray Perception as well.)

(I don't necessarily worry about it that much, because the cost is probably pretty close to what it should be.)

[prestidigitator]

I've always had a problem with the way Nightvision is built. IIRC, it is simply +4 Vision, Only to offset penalties from darkness (the natural condition, not the Power Darkness).

If this is all it takes, then someone with plain old +4 really good vision sees in the dark as well as a person with base vision sees in the day.

Is it really only -4 for darkness? Does that mean with stars and moon or with no light at all like in a cave underground or in a closed dark room? If I spend the 5 points (CMIIW) for Nightvision, can I get up in the middle of the night and confidently walk to the bathroom and use the toilet without missing or tripping or stubbing my toe? Even if it isn't in a house I'm familiar with or if the furniture has been rearranged? Can I pick up a glass of milk off a table in a dark room without spilling it? Can I read a book in a dark room? I think it's a stretch to say that a mere +4 gives the equivalent of daylight vision in the total absense of light.

It seems to me that the ability to see in total darkness needs some other construct besides a bonus versus a penalty to a PER roll. What is needed is a way to say the caharacter gets a PER roll even when he normally wouldn't. (OT: The same thing applies to N-Ray Perception as well.)

(I don't necessarily worry about it that much, because the cost is probably pretty close to what it should be.)
I've always thought of a character with Nightvision as seeing as well in starlight (not moonlight) as a normal character during the day. With that in mind, a +4 to offset darkness penalties is probably reasonable (especially given the guideline that this is roughly, "16 times," better sight than normal).

However, it also means a character can't see in a dark cave unless there is some weak form of light around by which the character could normally see if it were strong (phosphorescent moss, distant torchlight, indirect filtered sunlight, etc.).

EDIT: Incidentally, in some games I make Nightvision apply to the whole Sight Group, rather than just Normal Sight. This seems more in line with the cost, and means a character with, for example, IR Vision might be able to see just fine in an underground cave where there is some weak geothermal heat but normally very little temperature differential.

[Gaelinic]

I've always thought of a character with Nightvision as seeing as well in starlight (not moonlight) as a normal character during the day. With that in mind, a +4 to offset darkness penalties is probably reasonable (especially given the guideline that this is roughly, "16 times," better sight than normal).

However, it also means a character can't see in a dark cave unless there is some weak form of light around by which the character could normally see if it were strong (phosphorescent moss, distant torchlight, indirect filtered sunlight, etc.).

EDIT: Incidentally, in some games I make Nightvision apply to the whole Sight Group, rather than just Normal Sight. This seems more in line with the cost, and means a character with, for example, IR Vision might be able to see just fine in an underground cave where there is some weak geothermal heat but normally very little temperature differential.

According to the FAQ, Nightvision works in total natural darkness including caves.

I just don't see why someone would buy Ultravision since the absence of any light is already offset by Nightvision. But I thank you all for your contributions.

[SirViss]

The only reason I would see that a character would buy UV Perception instead of Nightvision is character concept, or the GM saying that he doesn't allow it, or some such reason.

[Foxx!]

The difference is subtle.

Nightvision: Need not be thought of as it's own sense, but just a modifier that eliminates the penalties for darkness with normal vision. It can allow for color vision in any lighting condition, including total darkness. Some GMs may choose to limit the color vision by the amount of actual visible light available however (total darkness would be black and white, while twilight would still be relatively full color).

Ultraviolet Perception: Is a specific sense. When attached to the Sight Group, it allows one to see into the UV part of the spectrum (normally invisible to normal humans). Other than being able to see in the dark (with available UV light), you can see a number of marvelous things that are only visible in UV. Flowers and many insects have different pattern in UV, some clothing looks different (like under a blacklight, which is really just intense UV light) and in a superhero/high tech world, there are invisible things that can only be seen in UV, alarms using UV beams of light for sensors, covert communications using beams of UV light, etc. Also, if you are affected by a Sense Affecting Power that only affects your Normal Sight, you still have your UV Sight.

Thank you. :) Very clear and easy to understand.

Cheers!

[prestidigitator]

According to the FAQ, Nightvision works in total natural darkness including caves.

I just don't see why someone would buy Ultravision since the absence of any light is already offset by Nightvision. But I thank you all for your contributions.
I know. I was simply describing the way I play Nightvision. Once again an area in which I think the FAQ should be ripped up, wadded, and used as toilet paper.

BTW, there is no reason Nightvision and UV Vision have to give you similar perceptions. There may be things that are near to invisible in the UV spectrum. There may be normally transparent substances (such as glass) that are opaque or very close to it for UV light. As people have mentioned, sources of UV light may be limited. In summary, there are easy ways for the GM to balance these senses if (s)he does want to utilize both in the campaign.

[Dust Raven]

I've always had a problem with the way Nightvision is built. IIRC, it is simply +4 Vision, Only to offset penalties from darkness (the natural condition, not the Power Darkness).

If this is all it takes, then someone with plain old +4 really good vision sees in the dark as well as a person with base vision sees in the day.

Is it really only -4 for darkness? Does that mean with stars and moon or with no light at all like in a cave underground or in a closed dark room? If I spend the 5 points (CMIIW) for Nightvision, can I get up in the middle of the night and confidently walk to the bathroom and use the toilet without missing or tripping or stubbing my toe? Even if it isn't in a house I'm familiar with or if the furniture has been rearranged? Can I pick up a glass of milk off a table in a dark room without spilling it? Can I read a book in a dark room? I think it's a stretch to say that a mere +4 gives the equivalent of daylight vision in the total absense of light.

It seems to me that the ability to see in total darkness needs some other construct besides a bonus versus a penalty to a PER roll. What is needed is a way to say the caharacter gets a PER roll even when he normally wouldn't. (OT: The same thing applies to N-Ray Perception as well.)

(I don't necessarily worry about it that much, because the cost is probably pretty close to what it should be.)

Of course, a person that buys +4 to his Sight PER roll also sees that much better in daylight, while Captain Nightvision doesn't, but CN can see in total darkness while Supervision-Man can't. I figure it balances out.

P.S.: I'm not too sure about reading a book in total darkness. I suppose that technically, by the strict rules, you can, but I've never plaid it that way. Printed text uses shading and color to function, something that doesn't exist in total darkness. The character can still see objects, but everything is in grey shades representng texture and outlines for shapes.

[Dust Raven]

The only reason I would see that a character would buy UV Perception instead of Nightvision is character concept, or the GM saying that he doesn't allow it, or some such reason.

Not just concept, but there are some things that UV can do that Nightsight can't. Detecting UV light is the most generally obvious. Do a web search for Ultraviolet Light and see how it's used and where it can be found. Having UV is more useful that you might think.

Of course, if all you want to do is see in the dark, Nightvision is obviously better.

[PhilFleischmann]

Of course, a person that buys +4 to his Sight PER roll also sees that much better in daylight, while Captain Nightvision doesn't, but CN can see in total darkness while Supervision-Man can't. I figure it balances out.
Actually he can. Supervision-Man has a 15- PER roll in daylight, and at night he's at -4, leaving him with an 11- PER roll. Captain Nightvision has only the normal 11- PER in daylight, and the dark of night doesn't hinder him in any way, so he's still at 11-. SVM and CN both have the same PER roll in darkness. I'm not saying that it makes sense, but that's what the rules say.


P.S.: I'm not too sure about reading a book in total darkness. I suppose that technically, by the strict rules, you can, but I've never plaid it that way.
I wouldn't play it that way either, but the rules seem to indicate that the only game effect of total darkness is a -4 to visual perception. This means that a normal 11- vision guy can see in total darkness on a 7-. Generally, he'd probably have to make a new PER roll every phase, or at each step in the process of whatever he's doing that requires sight. If he is walking to the bathroom for example, a GM might make him roll for each turn in the hallway and each major piece of furniture that he needs to avoid bumping into. IIRC, the odds of a 7- are about 20%, which means he can, by the game rules, on average, do anything he could do in light if he takes five times as long to do it. And you are right if you think this makes no sense realistically.


Printed text uses shading and color to function, something that doesn't exist in total darkness. The character can still see objects, but everything is in grey shades representng texture and outlines for shapes.
Seeing objects also uses shading and color to function. You don't need to see color to be able to read. All you need is high contrast in brightness between the text and the page, such as black on white - no colors need be involved. Bright red on bright green is difficult to read even in full daylight, and could be impossible for someone who is colorblind. The ease of seeing outlines of objects depends on the contrast of the background (just like for text). This is how camoflage (sp?) works. It's hard to see a low-contrast item even in daylight, such as a contact lens or puzzle piece on a patterned carpet.

The problem is, IMO, that:
1. Total darkness should impose something more than just a -4 penalty. Perhaps it should be simply a bigger penalty, or perhaps it should be something in addition to a roll penalty. And
2. Darkvision should therefore be based on countering whatever the real effect of darkness is, not a mere -4 penalty.

[pinecone]

I've always treated "total darkness" as meaning "you cannot see", no differant than being flashed....I use the -4 for "its Real dark" but not for Totally dark....I guess its a style thing.....

[Dust Raven]

Actually he can. Supervision-Man has a 15- PER roll in daylight, and at night he's at -4, leaving him with an 11- PER roll. Captain Nightvision has only the normal 11- PER in daylight, and the dark of night doesn't hinder him in any way, so he's still at 11-. SVM and CN both have the same PER roll in darkness. I'm not saying that it makes sense, but that's what the rules say.
Just what I was saying, but in daylight supervisonman has better vision.



I wouldn't play it that way either, but the rules seem to indicate that the only game effect of total darkness is a -4 to visual perception. This means that a normal 11- vision guy can see in total darkness on a 7-. Generally, he'd probably have to make a new PER roll every phase, or at each step in the process of whatever he's doing that requires sight. If he is walking to the bathroom for example, a GM might make him roll for each turn in the hallway and each major piece of furniture that he needs to avoid bumping into. IIRC, the odds of a 7- are about 20%, which means he can, by the game rules, on average, do anything he could do in light if he takes five times as long to do it. And you are right if you think this makes no sense realistically.
I've ruled that the -4 for "total darkness" actually refers to what I've always called pitch black. Not lightless, but effectively lightless. So little light that there is no longer such a thing as contrast between objects. Total Darkness is total darkness, and anyone relying on light to see is blind. A character with Nightvision can see normally in the -4 pitch black "total darkness" as if he had normal lighting conditions (there there are still no contrast modifiers), and can see in real total darkness, but cannot distinguish color and there is no such thing as contrast; objects are nothing more than outlines distinguishable from their surroundings through whatever SFX defines the Nightvision.



Seeing objects also uses shading and color to function. You don't need to see color to be able to read. All you need is high contrast in brightness between the text and the page, such as black on white - no colors need be involved. Bright red on bright green is difficult to read even in full daylight, and could be impossible for someone who is colorblind. The ease of seeing outlines of objects depends on the contrast of the background (just like for text). This is how camoflage (sp?) works. It's hard to see a low-contrast item even in daylight, such as a contact lens or puzzle piece on a patterned carpet.
I suppose what I was getting at was contrast and forgot the word. :) Contrast is still a function of light though, and without light, there is no such thing as contrast (see my above comments).


The problem is, IMO, that:
1. Total darkness should impose something more than just a -4 penalty. Perhaps it should be simply a bigger penalty, or perhaps it should be something in addition to a roll penalty. And
2. Darkvision should therefore be based on countering whatever the real effect of darkness is, not a mere -4 penalty.

Agreed. I've always done the -4 thing for really really dark, nearly lightless environments, like an overcast moonless night in the wilderness. It's not total darkness, but for most of humanity, it might as well be. Actual total darkness has no light and normal vision is useless.

[Teflon Billy]

What would you do for active nightvision? (Where the character's eyes project some sort of radiation that is detectable by the persons eyes when reflected off objects. I'm using the old AD&D 2nd Ed. 60+' infravision for this concept.)

How would this be represented, just a SFX that permits nullification of the -4 PER penalty even in truly lightless environments? Or is there something else that is needed?

Would there be a cost difference for Passive Nightvision and Active Nightvision? (would the detectability aspect of active vision cancel out the penalty of passive vision not being able to see in total darkness)

TB

[PhilFleischmann]

Just what I was saying, but in daylight supervisonman has better vision.
No, that's not what you said. I'll quote you again: "CN can see in total darkness while Supervision-Man can't." This is the problem: If nightvision is bought as +4 vision, with the limitation only vs darkness penalties, then someone who buys straight +4 vision has the same PER roll in the limited circumstance. In the example, both guys have 11- sight PER in darkness. The same thing as would happen if Ocean Man buys +4 Vision, Only underwater. He and Supervision-Man, have exactly the same vision under water. OM and CN's vision bonuses apply only in a limited circumstance, which SVM's applies all the time.

There is nothing in the rules (that I've seen) that says that a normal vision guy can't make a PER roll at -4 in total darkness. And if you rule that normal vision is outright impossible, i.e., no roll allowed at all, there is nothing in the construct of nightvision that allows for an exception. It's just a bonus to sight with a circumstance limitation.

My claim is that total darkness (or even almost total darkness) goes beyond simply -X to sight PER. And along with that, darkvision needs to be built as something beyond simply a +X to sight PER, with the "Only vs. darkness" limitation.


A character with Nightvision can see normally in the -4 pitch black "total darkness" as if he had normal lighting conditions...
What about a character who has +4 Sight Perception, *without* the nightvision *limitation*? According to the rules, he should be able to see just as well in darkness, "total darkness," "pitch black," etc., as someone with Nightvision. Taking a limitation should not grant an advantage.


I suppose what I was getting at was contrast and forgot the word. :) Contrast is still a function of light though, and without light, there is no such thing as contrast (see my above comments).
I may have not understood what you meant by this point. Contrast is required to distinguish the outlines of objects, too, not just their colors. Contrast in not just to allow you to distinguish the red stripe from the white stripe on a flag, it also allows you to distinguish the edge of the flag itself from the background.


Agreed. I've always done the -4 thing for really really dark, nearly lightless environments, like an overcast moonless night in the wilderness. It's not total darkness, but for most of humanity, it might as well be. Actual total darkness has no light and normal vision is useless.
So Nightvision would be useless as well. That's fine. So what power would you use to allow someone to see in actual total darkness?

[prestidigitator]

Hmm. Technically there is no such thing as total darkness, for a small number of photons can actually tunnel through anything except an infinite potential difference (which cannot exist in reality, though large potential barriers may be modeled with an infinite potential difference). However, I think there will be a lot fewer than 2^-4 = 1/16 the photons (which is the condition under which I would impose a -4 penalty) in a completely sealed bunker, for instance.

If you want to be able to see in complete darkness, I would say you have to buy an active sense as part of the Sight Group, not a passive one. I believe all listed standard Sight Group senses are passive (though maybe you could define UV Vision or IR Vision as active?). Also, Spatial Awareness works in total darkness, and I think maybe you could just include it in the Sight Group. I don't know.

[Gaelinic]

What would you do for active nightvision? (Where the character's eyes project some sort of radiation that is detectable by the persons eyes when reflected off objects. I'm using the old AD&D 2nd Ed. 60+' infravision for this concept.)

How would this be represented, just a SFX that permits nullification of the -4 PER penalty even in truly lightless environments? Or is there something else that is needed?

Would there be a cost difference for Passive Nightvision and Active Nightvision? (would the detectability aspect of active vision cancel out the penalty of passive vision not being able to see in total darkness)

TB

It would be a visible effect for a zero endurance costing power. So you'd take a limitation, visible.

[schir1964]

It would be a visible effect for a zero endurance costing power. So you'd take a limitation, visible.
Actually, per the rules, Passive vs Active senses is a 0 Limitation/Advantage.

So being visible isn't worth any points, but that's per the rules.

- Christopher Mullins

[Teflon Billy]

It would be a visible effect for a zero endurance costing power. So you'd take a limitation, visible.In AD&D the active illumination was only visible to creatures that had infravision (active or passive), would this effect the right up? I think it would halve the limitation, IMO.

TB

[Dust Raven]

No, that's not what you said. I'll quote you again: "CN can see in total darkness while Supervision-Man can't." This is the problem: If nightvision is bought as +4 vision, with the limitation only vs darkness penalties, then someone who buys straight +4 vision has the same PER roll in the limited circumstance. In the example, both guys have 11- sight PER in darkness. The same thing as would happen if Ocean Man buys +4 Vision, Only underwater. He and Supervision-Man, have exactly the same vision under water. OM and CN's vision bonuses apply only in a limited circumstance, which SVM's applies all the time.

There is nothing in the rules (that I've seen) that says that a normal vision guy can't make a PER roll at -4 in total darkness. And if you rule that normal vision is outright impossible, i.e., no roll allowed at all, there is nothing in the construct of nightvision that allows for an exception. It's just a bonus to sight with a circumstance limitation.

My claim is that total darkness (or even almost total darkness) goes beyond simply -X to sight PER. And along with that, darkvision needs to be built as something beyond simply a +X to sight PER, with the "Only vs. darkness" limitation.


What about a character who has +4 Sight Perception, *without* the nightvision *limitation*? According to the rules, he should be able to see just as well in darkness, "total darkness," "pitch black," etc., as someone with Nightvision. Taking a limitation should not grant an advantage.


I may have not understood what you meant by this point. Contrast is required to distinguish the outlines of objects, too, not just their colors. Contrast in not just to allow you to distinguish the red stripe from the white stripe on a flag, it also allows you to distinguish the edge of the flag itself from the background.


So Nightvision would be useless as well. That's fine. So what power would you use to allow someone to see in actual total darkness?

I'm hoping this can be cleared up if I repeat one thing: My definitions of "total darkness" and the books definition of "total darkness" are different. What the book calls "total darkness" I call "really dark." What I call "total darkness" the book does not define.

As for the application of Nightvision, I don't assume it's just a +4 PER Only Versus Darkness Penalties for Sight PER Rolls. Yes, it cancels those penalties, but it also allows the character to see in what I call "total darkness." This is something that +4 to Sight PER Rolls-man can't do.

I should probably note that I've allowed characters to purchase Enhanced PER that only counters Darkness Penalties, and it costs less than Nightvision (I call it a -1 1/2 Limitation, so the cost is only 3 points) and is typically called "Lowlightvision."

[prestidigitator]

In AD&D the active illumination was only visible to creatures that had infravision (active or passive), would this effect the right up? I think it would halve the limitation, IMO.

TB
I would say that an active sense can, by default, be detected by anyone who possesses the same sense. For example, active IR Perception can be detected by anyone with IR Perception. Active UV Perception can be detected by anyone with UV Perception. Active Sonar can be detected by anyone with Sonar. If it is detectable by a whole Sense Group and maybe other senses as well, it could take a Limitation.

[PhilFleischmann]

As for the application of Nightvision, I don't assume it's just a +4 PER Only Versus Darkness Penalties for Sight PER Rolls.
But that's exactly how the book defines it! If you want it to give you something more than that, you either have to build it differently, or handwave it and say, "By GM fiat, Nightvision allows you to see in (total?) darkness better than non-limited +4 vision, somehow." The latter option may be the best course of action, but it isn't strictly by the rules.

[prestidigitator]

I think of nightvision goggles as simply giving you Nightvision through a Focus. They certainly don't allow you to see in complete darkness!

[Gaelinic]

In AD&D the active illumination was only visible to creatures that had infravision (active or passive), would this effect the right up? I think it would halve the limitation, IMO.

TB

What you're describing is not an active sense. From what I remember, the ability did not transmit in order to perceive. It was just described as a special effect of the infravision. That's why I'd just make it visible. But if it's only visible for people with infravision it might not be worth a limitation at all.

[Dust Raven]

But that's exactly how the book defines it! If you want it to give you something more than that, you either have to build it differently, or handwave it and say, "By GM fiat, Nightvision allows you to see in (total?) darkness better than non-limited +4 vision, somehow." The latter option may be the best course of action, but it isn't strictly by the rules.

Mmm... seems you're right. It is bought like that. :lol: All this time I just thought is was defined like IR and UV vision was, as a seperate Detect of some sort. Silly me.

Well then... I hand wave GM fiat the damn thing. It's a Detect Stuff In The Dark instead of a +4 PER In The Dark now. :p

[Kristopher]

I tend to go with a realistic approach and require the presence of some kind of light source, however dim, for Nightvision to function.

IMO, the difference between UV Vision and Nightvision is mainly one of SFX.

[Dust Raven]

Mmm... seems you're right. It is bought like that. :lol: All this time I just thought is was defined like IR and UV vision was, as a seperate Detect of some sort. Silly me.

Well then... I hand wave GM fiat the damn thing. It's a Detect Stuff In The Dark instead of a +4 PER In The Dark now. :p

I've been rereading this thread and decided to reevaluate this decision of mine. For the points paid for it, I think that Nightvision works just fine like it is (though I'm penciling in the definition of "overcase, moonless night" for the book's description of total darkness). The seeing in the dark power I'm imagining should probably cost 10 points (essentially Detect Physical Objects, part of the Sight Group, but using a different SFX than light to see by).

This still keeps UV and Nightvision pretty much in line with each other. They do the same thing, but each can be used in situations where the other cannot.

[Kristopher]

Theoretically, a sufficiently detailed form of IR vision should be able to see in total darkness (in terms of visible light) because of the very slight variations in radiant heat and IR reflectivity of different materials.

[PhilFleischmann]

I think of nightvision goggles as simply giving you Nightvision through a Focus. They certainly don't allow you to see in complete darkness!
In the real world, nightvision goggles aren't based on comic-book science. Real nightvision goggles work by shifting light in the infrared (or was it ultraviolet? I forget) spectrum into the visible spectrum which you can then see. Therefore, real-world nightvision goggles should be based on infravision (or untravision? I'm sure someone knowledgable will fill us in.) through a focus.

All vision is based on the presense of light of sufficient intensity. If the intensity is below a certain threshold, it won't trigger the nerve cells in your retinae to fire at all, and you therefore won't see anything. Some forms of enhanced vision could be defined as lowering the threshhold for some or all of the rods and/or cones in the retina, but even then, *some* minimum amount of light is still needed.


Theoretically, a sufficiently detailed form of IR vision should be able to see in total darkness (in terms of visible light) because of the very slight variations in radiant heat and IR reflectivity of different materials.
But what if the surroundings are all the same material? If you're in a cave, you won't be able to tell where the walls, floor, ceiling, stalactites, and stalagmites are, because they're all the same temperature. You might be able to see where you were just leaning against the wall, because it may have absorbed some of your body heat, but that's it.

So what do you buy if you want to see in *total darkness*? I want to walk around normally in a cave without bumping into the walls, tripping over ridges in the floor, falling through holes, banging my head on the low ceiling, etc. IMO, this should require some form of Spacial Awareness, as part of the Sight Group (so it's Flashed along with normal sight, block by all the things that block normal sight, won't work through opaque objects, won't work if your eyes are closed or you're blindfolded, etc.). You won't have to pay for Targeting or Discriminatory, since normal Sight already includes those things.

And while we're at it, I'll also mention the wierd way in which N-Ray Perception is built: There is nothing in the construct that allows it to percieve through barriers - the exact function it is supposed to have!

[schir1964]

...But what if the surroundings are all the same material? If you're in a cave, you won't be able to tell where the walls, floor, ceiling, stalactites, and stalagmites are, because they're all the same temperature. You might be able to see where you were just leaning against the wall, because it may have absorbed some of your body heat, but that's it...
I think, don't know for sure, but I think he was suggesting that your own body might give off enough IR to be reflected off the surfaces to enable you to distinquish them.

And push this concept further, not to say it is anywhere near realistic, the air currents in the cave could be seen since they wouldn't be the same temperature as the walls. And theoretically, the surfaces of the walls and floor might actually have enough variation in them to distiguish them. But this is all presuming that a person can detect changes in temperature that might be considered impossible in real life.

Just A Guess

- Christopher Mullins

[prestidigitator]

In the real world, nightvision goggles aren't based on comic-book science. Real nightvision goggles work by shifting light in the infrared (or was it ultraviolet? I forget) spectrum into the visible spectrum which you can then see. Therefore, real-world nightvision goggles should be based on infravision (or untravision? I'm sure someone knowledgable will fill us in.) through a focus.
That is a common mis-conception. Real world nightvision goggles are purely light amplification devices. They use the same (or near enough to the same as makes no difference) spectrum as our eyes do. Now there are infrared devices used in a similar fashion (you commonly see applications in helicopters used by police and for wildlife tracking), but these are not, "nightvision goggles."

[Kristopher]

In the real world, nightvision goggles aren't based on comic-book science. Real nightvision goggles work by shifting light in the infrared (or was it ultraviolet? I forget) spectrum into the visible spectrum which you can then see. Therefore, real-world nightvision goggles should be based on infravision (or untravision? I'm sure someone knowledgable will fill us in.) through a focus.

All vision is based on the presense of light of sufficient intensity. If the intensity is below a certain threshold, it won't trigger the nerve cells in your retinae to fire at all, and you therefore won't see anything. Some forms of enhanced vision could be defined as lowering the threshhold for some or all of the rods and/or cones in the retina, but even then, *some* minimum amount of light is still needed.


But what if the surroundings are all the same material? If you're in a cave, you won't be able to tell where the walls, floor, ceiling, stalactites, and stalagmites are, because they're all the same temperature. You might be able to see where you were just leaning against the wall, because it may have absorbed some of your body heat, but that's it.

So what do you buy if you want to see in *total darkness*? I want to walk around normally in a cave without bumping into the walls, tripping over ridges in the floor, falling through holes, banging my head on the low ceiling, etc. IMO, this should require some form of Spacial Awareness, as part of the Sight Group (so it's Flashed along with normal sight, block by all the things that block normal sight, won't work through opaque objects, won't work if your eyes are closed or you're blindfolded, etc.). You won't have to pay for Targeting or Discriminatory, since normal Sight already includes those things.

And while we're at it, I'll also mention the wierd way in which N-Ray Perception is built: There is nothing in the construct that allows it to percieve through barriers - the exact function it is supposed to have!

Real nightvision systems work by sensing ambient light, processing it, and displaying an image. Some of them will detect light from outside the part of the spectrum visible to humans, but only as a means of taking in more ambient light. Not all of the newer nightvision systems are susceptible to bright or sudden lights -- some of them will adjust or filter.


Heat is radiated as infrared (IR), which is just another form of electromagnetic radiation, just like visible light, but lower in frequency than visible light, (and higher in frequency than microwaves and radio). Just as with visible light, different materials and textures will reflect and absorb IR radiation differently. Theoretically, your own radiant heat might even be enough to illuminate a room if your eyes are sufficiently sensitive.

[Dust Raven]

That is a common mis-conception. Real world nightvision goggles are purely light amplification devices. They use the same (or near enough to the same as makes no difference) spectrum as our eyes do. Now there are infrared devices used in a similar fashion (you commonly see applications in helicopters used by police and for wildlife tracking), but these are not, "nightvision goggles."

Well, the term "nightvision" refers to any device that allows you to see at night, which would include light amplification (called lowlight) and IR enhancment. A few use UV enhancement, which sometimes works better because our retinas are designed to pick up UV, but our corneas filter most of it out so it is still mostly invisible to us. All these devices are nightvision, with the most common being lowlight/light amplification.

[Dust Raven]

And while we're at it, I'll also mention the wierd way in which N-Ray Perception is built: There is nothing in the construct that allows it to percieve through barriers - the exact function it is supposed to have!

Personally, I believe that N-Ray should be an adder/enhancment rather that it's own sense. Technically, the way it's bought, normal Sight should also be able to see through walls.

[PhilFleischmann]

Personally, I believe that N-Ray should be an adder/enhancment rather that it's own sense. Technically, the way it's bought, normal Sight should also be able to see through walls.
Exactly!

And Re: How Nightvision goggles work in the real world, it appears I was mistaken. I'm glad to learn about this stuff.

I stand corrected, but that's only because I'm wearing orthopedic shoes.

[Killer Shrike]

According to the FAQ, Nightvision works in total natural darkness including caves.

I just don't see why someone would buy Ultravision since the absence of any light is already offset by Nightvision. But I thank you all for your contributions.

Why buy a hammer when you can pound a nail with a wrench?

Point is, they're two different tools, and though there might be some overlap in their capabilities, they are tailored to do different things.


Nightvision is literally just like PSL's to offset darkness penalties.

UV Vision is the ability to percieve into a range of light normally beyond the ken of normal sight.

Practically they both happen to permit one to see in the dark, but they have variant pros and cons. Like the hammer is more specialized to pounding nails compared to the wrench, Nightvision is more specialized to seeing at night -- it's even in the name. That doesnt mean it's better than UV Vision overall, it's just more tailored to a specific effect.

The UV Vision situationally will let you do the same thing, but not as easily (requires a source of UV light), nor as safely (if you happen to be carrying around a source of UV light youre basically running up a flag to any other UV enabled people). However it also lets you see and do things that Nightvision doesnt do, which the clever player could capitalize on.

For instance, UV might have some forensic uses that Nightvision lacks, will see better underwater since UV light penetrates water deeper than normal light, could be used in conjunction with some blacklight paint (or similar) to leave signals for teammates w/ UV equipment that arent seeable by a large majority of people, and so forth.

Dont write UV Vision off as useless; just realize that if all you want to do is see better at night then Nightvision is probably the better choice.