[Basic] Advantage of the Week: Hyperspectral Vision, Infravision and Ultravision

[johndallman]

Infravision [0 or 10] is an exotic physical advantage, allowing you to see in the infra-red range of the electro-magnetic spectrum, rather than the normal visual range. It appeared during the GURPS 3e period, although I’m not sure just where, and its cost changed at 4e. If you can only see in the infra-red, and not at all in the visual, this is a [0] feature; if you can see in both infra-red and visual, it costs [10].

Ultravision [0 or 10] is much like Infravision, except that it applies to the ultra-violet range. It appeared at GURPS 4e.

Hyperspectral Vision [25] lets you see in the infra-red, visual and ultra-violet ranges. It costs more than Infravision plus Ultravision, because it is better: the combination often reveals details that are unnoticeable in a single range. This advantage appeared at GURPS 4e, based on the capabilities of real-world TL7+ sensors. It had a 3e predecessor, Spectrum Vision, which can be built with special enhancements to Hyperspectral Vision.

Infravision lets you fight at no penalty in darkness, if your opponent is warmer than the surroundings, as living creatures and most machines are. You get +2 to Vision rolls to spot warm things, and +3 to Tracking for trails left by them under an hour ago. You can’t distinguish colours with Infravision, nor fine details of size or shape (roll at ‑4 to tell similar things apart). Reading by reflected infra-red is possible, with a Vision‑4 roll. You can be dazzled by sudden flashes of infra-red, in the same way as normal vision is by flashes of light.

Ultravision gives you enhanced colour perception, if UV light is available. Sunlight provides it, even if diffused by clouds, as do florescent lamps, but normal fires, candles and incandescent lamps don’t. Ordinary glass blocks UV, but forensic and medical UV lamps are available at TL7+. You get +2 to all Vision rolls if UV is available, and to Forensics, Observation and Search rolls made to spot things. At night, outdoors, there is a little UV from starlight, which reduces your darkness penalties by 2, cumulative with ordinary Night Vision. UV penetrates water better than visible light, halving penalties for less-than-total darkness underwater.

Hyperspectral Vision gives +3 to all Vision and Tracking rolls, and to Forensics, Observation and Search rolls made to spot things. You have no vision or combat penalties due to darkness if there is any light at all, like Night Vision 9. In total darkness, you have the benefits of Infravision. You can’t have Infravision or Ultravision in addition to this trait, since it’s a better version of both of them.

There are two special enhancements for Hyperspectral Vision, both +30%, and neither appropriate for real-world sensors. Extended Low-Band allows you to see microwave, radar and radio radiation, although it doesn’t help you understand radio signals. Extended Low-Band allows you to see X-ray and gamma-ray radiation. Adding both of these gives 3e Spectrum Vision.

High-tech settings provide characters with Infravision and Hyperspectral Vision via equipment, possibly combined with Telescopic Vision. Technological attacks with Homing often use these traits. Fantastic settings make all of these advantages racial or mutant abilities. Bio-Tech can provide them all, although at quite high TLs, and DF offers them via familiars. High-Tech has IR and UV photography and camouflage, and Horror has all-seeing opponents. Magic clarifies interactions of these advantages with spells, while Powers and Enhanced Senses add details.

Psionic Powers can affect the mind behind these senses, and Social Engineering gives bonuses to Body Language skill. Standard Spaceships passive sensors have Hyperspectral Vision, and Zombies often have Infravision.

I think I’ve only used these abilities in games via high-tech equipment. What have they done in your games?

[whswhs]

Enhanced Senses specifically distinguishes between near IR and thermal IR as giving different advantages and disadvantages.

[Anthony]

My big problem with these advantages is that two of them are outright wrong.

The effects of ultravision are wrong -- UV doesn't help much in low light situations, is worthless underwater, and while it can help with color perception, the effects are overstated.

Hyperspectral vision should probably have stuck with its 3e name, because it's unrelated to real-world hyperspectral sensors.

[RogerBW]

"Hyperspectral" as implemented in GURPS has always felt a bit like one of those things that sounded like a neat edge-of-the-future idea when the relevant book was being written, but has turned out not to work that way – like AESA in 3e Vehicles (yes, I know there's a real thing called that, but again it doesn't work like that in reality), or the arm guns in Transhuman Space.

I don't think I've ever played a character with any of these as an innate ability.

[AlexanderHowl]

A more realistic version of UV would focus on the contrast between reflected normal light and reflected UV light. It effect, it should give a +1 to any IQ-based or Per-based roll where detecting any type of visual contrast, damage, or flaw would be beneficial. The bonus would apply to the following skills whenever UV light is available: Armoury, Artist, Camouflage, Carpentry, Cooking, Counterfeiting, Electronics Repair, Forensics, Jeweler, Leatherworking, Machinist, Makeup, Masonry, Mechanic, Naturalist, Observation, Pharmacy, Poisons, Scrounging, Search, Shadowing, Sewing, Smith, Survival, Tracking, and Urban Survival.

[Phil Masters]

I have a nasty feeling that Ultravision may appear in GURPS because it showed up in D&D at some point as a kewl symmetrical thing to infravision. Old-style fantasy games were very big on kewl symmetries with thin technobabble justifications. And “Infravision” appears in such games as a thin technobabble justification for the Uncanny Ability(TM) of dwarfs and elves to see in the dark.

I’ve surely played fantasy characters at some point with such advantages in their racial templates, because they are common as such. But I don’t recall ever using them much in play.

This is probably one of those points where the GM should have the option to set a big “Realism” vs. “Fantasy Convention” toggle switch when the campaign is being conceived, and depending how the switch is set, you’d use two completely different sets of advantages and rules.

[ericthered]

In lawmen of borlo a large number of templates had these traits. Despite being focused on detectives solving crimes, the traits almost never came up.



Realistically, the skill boosts in the modern world should be replaced by tools. The advantage of the UV vision trait for forensics is the ability to use it constantly and passively. If its obvious there is a crime scene and people have access to all of their tools, it probably shouldn't give a bonus.



The vision bonuses may be especially appropriate if the character is trying to beat (search, forensics vs housekeeping) another character without the vision.



Most non-mammalian vertebrates have light uv-vision, able to see a spectrum just above violet.

[khorboth]

Combining vision advantages an yield extra effects too.

I made a 3e gadgeteer who could see the entire spectrum. I added microscopic vision, independently focusable eyes and one level of penetrating vision. With that, he could read floppy disks. It was the 90s. That same combo should let someone read a flash drive too, though. Slowly. With an appropriate skill.