UV and IR vision

[Tahlorn]

Alright, everyone has a firm grasp on what we can see and the limitations of normal visible spectrum vision. But what of IR and UV?

IR allows one to see heat radiation. If something is wearing a thermal bodyglove, does it make it harder to spot in IR? Can a character with IR make out fine details (engraved letters, buttons, etc.)? You definetaly would be unable to read any form of writing, which brings on many problems. M yfavorite is that IR has a hard time going through glass (thus the rgeenhouse effect), so I make it harder for things with IR vision to look through windows.

And what of UV? Sure, you know where not to go to avoid a sunburn, and can spot a Defel easier, but what about everything else? We use UV to look at the sun better and distant stars for the radiation, but what other advantages would you get? And can one hide in the shadows form UV vision, or be masked from UV rays?

Thanks for any info that you can chuck at me!

~Tahlorn

[Argamoth]

It depends if the ink reflects IR in relation to whatever it's printed on. As far as I know, IR vison would make everything that gave off heat a light source. That's why they can see in the dark.

Don't know too much on UV though.

[K_Feldspar]

I guess I would just make sure to know if the aliens get IR/UV in addition to regular vision or can only see in those limited spectrums.

Otherwise in the real world... UV is also used to detect certain minerals. Many flowers have paterns in the UV spectrum that humans can't see. Detectives also use UV light to find blood stains etc. A UV seeing character might consider carrying around a special UV glowrod for dark spaces. Perhaps these can be extended can be into your campaign world.

Only thing I can think of for IR is that some consumer electronics use IR to communicate. It must be line-of-sight, and has a short range.

Creatures using either of these might have all their equipment readouts in these spectra making them unreadable to humans. Maybe even blasters use different frequencies. I've already mentioned in another thread how my PCs always want to play a defel with a UV lightsaber.

[entropy]

There's more to IR than thermal radiation, though most (if not all-I don't know where black-body radiation falls) heat falls into IR. At the high end of the IR scale is the block used for active night vision. This basically works like a IR glowrod would for a character who could see that spectrum. The light would be invisible to most races, but bright and obvious to anyone with IR detecting equipment. IR is a fairly large spectrum, an ambitious GM could divide it up and say that certain creatures see different portions of the spectrum, and devices such as night vision, IR communications, and remote controls work in another, with full or no overlap.

Another neat thing about IR is that in todays world, a lot of materials we think of as opaque or translucent are transparent to IR. Sony once had to do a rapid recall of one of their night vision video cameras when they found out it could see through some types of clothing. Things like window tinting and those black plastic domes that hold cameras in shopping centers or casinos are also transparent to IR. Of course in a universe where aliens can see IR, a GM could certainly rule that this is not the case.

UV often has the opposite problem, with the windows of many office buildings, automobiles, and things like sunglasses specifically designed to pass very little UV. I would think that normal starfighter cockpits would almost certainly block UV light, as the suntan you get when outside the atmosphere must be really nasty. If you could only see in UV, areas where normal people see fine could be completely dark to you. This might be an interesting trick to play on the defel in your party. Remember, those special goggles don't let them see normal wavelengths, they block out the non-UV. As with IR htough, it's a broad spectrum, feel free to divide it up as you see fit.

[garhkal]

I usually run it, that IR sees heat signatures, and UV is like lowlight.
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