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Old 01-05-2023, 11:42 AM   #1
thom
 
Join Date: Oct 2011
Default Distance for Hearing/Vision rolls?

OK, in my Fantasy campaign, I've got a Hearing/Vision contest coming up in my next session, and I want to do it right.
Situation: PC on night watch for a caravan, and a 10-man group of orcs (with Night Vision 5) is heading towards the PC for an attack.

• the Orcs are not using stealth; they're moving at Speed of 4.
• I'm figuring this gives a +2 on hearing them, accounting for the size of the group.
• It's a cloudy night, so -4 to the PC's Vision rolls.
• the PC is standing behind a torch, and doesn't have any Night Vision (I'm expecting they'll learn from this mistake-assuming they survive <eg>)

With a Perception of 12, and +2 for hearing based on group size, and -4 for a cloudy night; IF the PC rolls a '12' HOW FAR AWAY does he see or hear the orcs??

thom
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Old 01-05-2023, 12:15 PM   #2
Varyon
 
Join Date: Jun 2013
Default Re: Distance for Hearing/Vision rolls?

If he's standing behind the torch, his night vision is nonexistent. The torch itself, based on the "Illumination Levels Table" from Powers: Enhanced Senses*, produces light that gives a -1 to see at 1 yard away, and a further -1 per +2 SSR to Range - -2 at 2 yards, -3 at 5 yards, and -4 at 10 yards, at which point there's no difference between the light from the torch and the ambient light (which is also -4)... but I'd apply a -2 beyond that 10 yards, on account of the character has non-adapted night vision (because he's staring at a torch). The orcs are in plain sight, for +10 to see them, and a net +4 (not counting Range) if further than 10 yards away, net +6 if further than 5 yards away, net +7 if further than 2 yards away. For a roll of 12 to succeed, the character's effective Sight needs to be 12; net +4 would negate -4 for Range, which conveniently is 10 yards away. So they'd be spotted around 10 yards away - unless you decide to treat them as easier to see due to the size of the group; 10 orcs could potentially be justified as being up to SM+4 (10x the size of a typical orc) if they're all walking side-by-side; I'd call them SM+2 instead, in which case they'd be spotted around 20 yards away.

In terms of noise, I don't currently have access to the Hearing Table (from High Tech as well as Powers: Enhanced Senses), but a bit of searching online indicates a "normal conversation" (which further searching puts around 60 dB) can be heard at 1 yard with a roll against Hearing+0, and I know it's +2 SSR to Range or -10 dB per -1 to Hearing. If the orcs are talking, then if they're all talking things might rise to around 5x as loud as that "normal conversation," which is around +25 dB - +2 to Hearing at 1 yard. Most likely they aren't that loud, but let's go with that. At +2 to Hear at 1 yard, and -1 per +2 SSR to Range, a roll of 12 for a character with Hearing 12 would result in them being detected at 5 yards away.

So, they'd be seen before they are heard, if I'm remembering the Hearing rules correctly (if you haven't received other responses by then, I'll try to remember to check my books when I get home and give you an update), and would probably be seen at around 20 yards away. Note they'll see the caravan much sooner than that, as that torch will be visible from a long ways off.

*EDIT: There's some language in the table about having a light source in a dark area rendering you unable to see outside of the illuminated area at all, but without further guidelines, I don't really know how to use that, so I'm ignoring it here.
EDIT2: Considering the character is making the rookie mistake of having the torch in front of him while on watch, does he happen to have any relevant skills such as Soldier? If so, I'd be inclined to allow an IQ-based roll for the character to realize that's not a good idea.
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Last edited by Varyon; 01-05-2023 at 12:25 PM.
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Old 01-05-2023, 03:31 PM   #3
thom
 
Join Date: Oct 2011
Default Re: Distance for Hearing/Vision rolls?

Quote:
Originally Posted by Varyon View Post
If he's standing behind the torch, his night vision is nonexistent....
*EDIT: There's some language in the table about having a light source in a dark area rendering you unable to see outside of the illuminated area at all, but without further guidelines, I don't really know how to use that, so I'm ignoring it here.
EDIT2: Considering the character is making the rookie mistake of having the torch in front of him while on watch, does he happen to have any relevant skills such as Soldier? If so, I'd be inclined to allow an IQ-based roll for the character to realize that's not a good idea.
OK, so let's put him 2 yards to one side of the torch - how does that improve things? I kinda figured spotting the orcs is gonna be more likely than hearing them - especially without any hearing advantage...
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Old 01-05-2023, 04:53 PM   #4
Varyon
 
Join Date: Jun 2013
Default Re: Distance for Hearing/Vision rolls?

At my books now, looks like my only error there was that I forgot Hearing ranges don't follow SSR, but are true doublings. Turns out that even if they aren't talking, someone who isn't trying to be stealthy would probably be around 60 dB, as the table in Loudness Levels (P:ES21) notes this is where a failed Stealth roll would be. If we treat it as around 80 dB for there being a group (equivalent to a loud conversation; note 90 dB is for a shout, and that's probably too loud for just ten orcs walking), it's an unmodified Hearing roll at 4 yards.

For vision, there actually aren't any rules related to where the light source is at (I was misremembering, and going off of a playtest-formatted version of the Illumination Table - from when we were discussing errata on the forums - which wasn't quite as readable as the publication-formatted version in Powers: Enhanced Senses), so it being behind you, in front of you, to the side, etc, doesn't matter. The text states the +10 for Plain Sight only applies within the illuminated area, and that you're at -7 to see anything outside of it... but doesn't define what the illuminated area is. Is it the area where the light source makes a difference? That seems rather excessive - a 120W lightbulb (+0) being on within your line of sight during Sunset (-1) certainly shouldn't make everything more than a yard away from that lightbulb be at -7 to see! Is it everything the light reaches? The light reaches everything if there isn't something in the way (in fact, going off of the Illumination Table, the only way to actually have a -10 to see is if you're in an area that is completely enclosed by light-blocking barriers). Without clarification, I'm going to ignore that rule.

So, ultimately, I think that the -2 I assumed beyond 10 yards shouldn't be in play. Again, light levels with a torch are at -1 at 1 yard, -2 at 2 yards, -3 at 5 yards, and -4 beyond that. Orcs who aren't sneaking should count as in plain sight, for +10 to see them, so beyond 5 yards we're at a net +6 to Vision, ignoring Range. This means a roll of 12 for a character with Vision 12 will spot an orc at 20 yards away. If we give the orcs an effective +2 to SM for there being 10 of them, they'll be spotted 50 yards away.
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Old 01-05-2023, 05:48 PM   #5
whswhs
 
Join Date: Jun 2005
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Default Re: Distance for Hearing/Vision rolls?

I think the question is, not "are you within the circle it illuminates?" but "are you looking at the light source?" If that light source is within your field of vision, your eyes will adapt to it, and thus be handicapped in seeing things that are darker.
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Old 01-05-2023, 08:10 PM   #6
Varyon
 
Join Date: Jun 2013
Default Re: Distance for Hearing/Vision rolls?

Quote:
Originally Posted by whswhs View Post
I think the question is, not "are you within the circle it illuminates?" but "are you looking at the light source?" If that light source is within your field of vision, your eyes will adapt to it, and thus be handicapped in seeing things that are darker.
Are you saying the rule from Powers: Enhanced Senses is meant to be something like "You are at +10 to see the light source, as it counts as In Plain Sight, but are at -7 to see anything else, in addition to any darkness penalties"? That still runs into the "lightbulb at sunset" issue. Or would you need to be close enough to the light source that you are more visible than you would be with ambient light alone for this to come into play - I could certainly buy that having a 120W lightbulb only a yard from your face blinds you to everything else.
EDIT: On second thought, that doesn't quite work either - a quick bit of reality checking shows me that I can still see things elsewhere in my room even when looking directly at the computer monitor, which is by far the brightest thing here (when it goes off, the only notable source of light is the dimly-glowing LED on my PC). Certainly I can see things in my room better when just using the light of the monitor rather than looking directly at it, but I wouldn't say by any more than would be covered by the -2 for my eyes not being appropriately adjusted.
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Old 01-08-2023, 12:13 AM   #7
Kaslak
 
Join Date: Oct 2022
Default Re: Distance for Hearing/Vision rolls?

Quote:
Originally Posted by thom View Post
OK, in my Fantasy campaign, I've got a Hearing/Vision contest coming up in my next session, and I want to do it right.
Situation: PC on night watch for a caravan, and a 10-man group of orcs (with Night Vision 5) is heading towards the PC for an attack.

the Orcs are not using stealth; they're moving at Speed of 4.
I'm figuring this gives a +2 on hearing them, accounting for the size of the group.
It's a cloudy night, so -4 to the PC's Vision rolls.
the PC is standing behind a torch, and doesn't have any Night Vision (I'm expecting they'll learn from this mistake-assuming they survive <eg>)

With a Perception of 12, and +2 for hearing based on group size, and -4 for a cloudy night; IF the PC rolls a '12' HOW FAR AWAY does he see or hear the orcs??

thom
For hearing rolls, as an alternative, you might consider also the alternative rules in Mysteries, making use of the SSRT instead of doublings.

The focus there seems more about recognizing the sound, and what a witness can describe, also based on his attention level, but I like to use them in general.
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