Dark Vision (60 ft.)

[Anders]

A classic in certain other games is the range-restricted sense - Darkvision 60 ft. Infravision 30 ft. etc. How much of a limitation should this be? I'm tempted to use the SSR table in some way, but I'm not sure how.

[Sam Baughn]

Power-Ups 4 has 'Increased Range, Line of Sight'. It seems like you should be able to 'reverse engineer' that to turn an advantage which normally has LoS range into one with a fixed maximum range. Since it is a +0% enhancement to change from a 2,000 yard range to line-of-sight range, we can extrapolate that into it being a -0% limitation to go the other way, after which you should be able to add 'Reduced Range' as normal.

[Anthony]

The Warp ability has a maximum range limitation which could be cribbed.

[Anders]

I thought about using the Warp mechanic, but it gives a -45% limitation for 60 feet, and that is much too severe.

[Taneli]

What's your typical maximum vision range? Take that, and then apply the reduced range limitation?

As an alternative, you could think about the various applications of vision, and the consider how various aspects of vision are lost as it's range decreases, and then apply that as a limitation.

[Anthony]

Originally Posted by Anders

I thought about using the Warp mechanic, but it gives a -45% limitation for 60 feet, and that is much too severe.

Actually, if you copy the text, it gives a -20% ((10 - distance penalty)*5%; distance penalty at 20 yards is -6) and no limitation beyond 100 yards.

[RedMattis]

I usually use the Accessibility guidelines when creating new limitations like this.

In other words, how useful/often is this useful is this compared to full Dark Vision?

18 meters is far enough to be... mostly sufficient in unlit indoor situations, excepting cathedrals or long escape-tunnels etc. Useful almost all of the time: ~-10%

Outdoors it is a bit worse, but it won't hinder you much in a forest where visibility was poor to begin with. Useful almost all of the time: ~-10%

On an open field or long street where you want to identify and shoot at someone with a bow or gun it is much too short compared to the ranges you might choose to engage someone (up to 50 meters or so). It also doesn't let you spot faraway ambushes. Useful roughly half the time: ~-20%.

It is almost completely useless for spotting flying enemies or anything going on in the skies. ~-40%

I generally tend towards the higher values to encourage actually using limitations like this, so I think I'd go with -20% for Dark Vision limited to 18 meters. It is easy enough to work around the limitations, but it does meaningfully limit the character especially in situations outside of their control.

[Varyon]

Originally Posted by Sam Baughn

Power-Ups 4 has 'Increased Range, Line of Sight'. It seems like you should be able to 'reverse engineer' that to turn an advantage which normally has LoS range into one with a fixed maximum range. Since it is a +0% enhancement to change from a 2,000 yard range to line-of-sight range, we can extrapolate that into it being a -0% limitation to go the other way, after which you should be able to add 'Reduced Range' as normal.

I like this, although it does mean the shortest range you can have (without making use of the option to set it lower at no further discount) is 200 yards. In theory you could extend the table - in this case, 200 yards would be -30%, 100 would be -40%, 50 would be -50%, and so forth. Considering that requiring a character to touch something to be able to see it with Dark Vision would only be -35% (Melee, C, Cannot Parry), however, such pricing may be inappropriate.

EDIT: It occurs to me it might not be a horrible idea to change things up a bit here - instead of using Reduced Range, assume the "original" ability already had the range you're wanting, and apply LOS in reverse. 60 yards rounds down to 50 yards on the table, which is +50% as an Enhancement. Reversing this, instead of x1.5 the price is ~x0.7, or -30%. Have a table.

Range	Discount
<5	-50%
5	-45%
10	-40%
20	-35%
50	-30%
100	-25%
200	-20%
500	-15%
1000	-10%
2000+	 +0%

This still has the issue of being cheaper than Melee, but let's be honest - needing to touch a target to be able to see it in the dark is probably worth a lot more of a discount than -35%.

[Anders]

I like RedMattis approach best so far. I think I'll go with that.

[Anaraxes]

Originally Posted by Taneli

What's your typical maximum vision range?

NOAA (for aviation purposes) puts the average for the northeastern US as between 2-3 miles (winter and summer). 7+ miles is considered "unlimited" visibility in that community. So you might go with either 15,000 yards (range band -23) or 5,000 yards (-20) for a GURPSish maximum from which to start limiting.

But there's no doubt a dozen different sources with their own conventions for practical useful visibility to use as a base.