GURPS Vision Powers

 GURPS has several sensory powers, lets take a loot at the vision based ones.

Acute Vision

A simple bonus to the perception roll for seeing things. This is a cheap alternative to increasing Per, though if increasing more than one sense Per is a better purchase. A few levels are reasonable for normal people, higher levels require exotic explanation.

Clairsentience

A pricey power, typically magic or psychic in nature. Lets you see from a different location, including the other side of a wall. Range is just 10y but can be doubled by spending a FP or add Increased Range for about double distance at 5/level. Really its *2, *5, *10, *20, *50, etc.

Dark Vision

This is the ability to actually see even in pitch darkness with no light source at all.

Hyperspectral Vision

A combination of Infravision and Ultravision this wide spectrum vision allows good vision in very low light conditions and bonuses to certain skills for the additional details.

Infravision

This is advanced thermographic vision, allowing finer details than modern equipment, Lets see see warm objects in the dark.

Nightvision

Simply cancels the penalties for darkness, though you still must have light to see by.

Penetrating Vision

This is the classic X-ray vision, allowing you to see through or inside something as easily as you can see it. Of these its the only one I am not fully happy with. Each level allows seeing through up to 6 inches of solid matter. The first level is an incredible value, imagine being able to see inside a person your examining, looking over someone for concealed weapons, or inside a device to see what needs repair. That is a huge boost to quickly knowing what is going on!

However seeing 12" is not much more powerful than 6" and this ability goes up at 10/level with each level granting another half a foot.

It is faster and easier to use than Clairsentience and has a few other perks too, though only covers vision. That first level may be underpriced but it is an exotic ability so I am ok with that.  However I long thought it should use a log increase in range, originally using the Size and Speed/Range table but now think each level should increase range as per Increased Range. This would cost 10 points per doubling as opposed to the 5 points/level of Clairsentience so lose ground as for max distance but has certain advantages.

Compare Clairsentience [50] and Penetrating Vision 5 [50]

Clairsentience lets you see up to 10y, 20y with 1 FP but takes a minute and an IQ roll.

Penetrating Vision 5 lets you see through up to 100" (8 feet) of solid object but do so casually with no IQ roll and the intervening material is kind of a vague outline that does not interfere with your sight. You cant see through as thick a wall but that wall does not have to be close either. You need to add another sight (Darkvision, Hyperspectral Vision, Infravision, or Ultravision) to see inside a dark object, like several inches inside the human body.

Penetrating Vision is a good choice over Clairsentience when you want to see quickly and can see through a bunch of discrete separate objects if the actual thickness does not exceed your capacity. This makes it superior for seeing through smoke clouds, fog, murky water, etc. Clairsentience is superior if range is your primary concern (even with my suggested modification).

Telescopic Vision

This can be used in two ways. To focus on a distant subject and cancel range penalties with tunnel vision as a side effect; or to scan an area reducing range penalties by half as much. It also acts as a scope, increasing ACC by up to double the base ACC.

Ultravision

This lets you see in very dim light and grants bonus to certain skills because you can see in the ultraviolet. For example many insects fluoresce and can be readily spotted.