How far can a person see in limited visibility

[garrowolf]

I've been trying to find an accurate but simple table that shows how far a person can see in various levels of darkness or limited visibility. I want to do it without increments. Just a simple table that people can reference.

 

[UngainlyTitan]

I've been trying to find an accurate but simple table that shows how far a person can see in various levels of darkness or limited visibility. I want to do it without increments. Just a simple table that people can reference.

In Ireland, at night with full cloud cover and no moon I cannot see my hand at the end of my arm at full extension. Though I might it I held it between me and the sky. Not tested that one.

With full moon and little cloud I can see quite clearly at 200 meters or so. More with object silhoutted on higher ground but I cannot see in to any shadow.

Every thing else is inbetween, a lot also depends on what you are looking for. I used to be a farmer, one night my Aberdeen Angus cattle broke out from their shed and even on a starlight night with a powerful lamp I could not see the animals owing to their glossy black coat. Unless they were looking at me, when their eyes reflected the light.
I could also spot them if I lay down on the ground and silhoutted them against the night sky.

On full snow cover on a full moon and a clear sky it is almost as good as daylight but again the shadows wil be impenetrable.

One other thing, far away sources of bright light can ruin you night vision without contributing anything to illumination.

Silhouetted
Silhouetted

 

[Janx]

once again, you're trying to simplify that which is complex.

My wife is near-sighted and considered legally blind without her glasses.

she can't see jack taco in the dark, nor can she navigate the house in the dark

I am far sighted, yet can read without glasses, and can see in the dark fairly well and can navigate my house with my eyes closed.

I find it ironic that the legally blind person can't function as a blind person, yet the awesome vision person totally rocks as a blind person.

Factors to consider:
individuals ability to see well in the dark (per my example)
indiividuals ability to navigate environments in the dark (not the same as 'seeing')
level of lighting
speed of adjustment to sudden light changes (going from light to dark)
nature of that which needs to be seen (size, color, reflectiveness, contrast with surroundings)

My old white chow stuck out like a ghostly blob in the dark. My new dog is mostly black, and she's pretty hard to see.

if they're just lying on the floor, not so easy to see. If they are in front of the window or another big object, I see contrast and can deduce what they are.

In college, we used to play NerfWars in this old victorian mansion I lived in. At night. In the dark, so we'd move slower. It was a stealth game, moving silently and sniping. I can't say the distances involved, but I could see movement for the longest LOS I could get in the house.

 

[ExploderWizard]

Without any increments you are effectively saying that seeing through any obscurement is the same at 5 feet or several hundred yards. Distance would be my starting point for making such modifiers.

 

[Stormonu]

I've been trying to find an accurate but simple table that shows how far a person can see in various levels of darkness or limited visibility. I want to do it without increments. Just a simple table that people can reference.

From the 1E Wilderness Survival Guide. Distance is in yards. Don't ask me what orifice they pulled this out of, but the supplemental text was pretty thorough.

----------------------Daylight---Twilight---Moonlight---Darkness
Clear 500 300 50 25
Overcast 400 250 50 25
Moderate Fog 150 100 25 15
Heavy Fog, Rain, Snow 50 30 15 10
Heavy Snow 35 25 10 5
-with Wind 35 25 10 5
Blowing sand/dust 20 20 10 5

er, does anyone know how to make this stay line up?

 

[howandwhy99]

500 yards is what I've heard too for average human vision to recognize a human face (also of normal size).

When you say limited now we're talking "limited by what?"

Cover is like saying I can see to the wall next to me and not beyond. The distance is me to the cover.

Seeing from a gas into liquids is covered by Snell's law.

Concealment is basically fog, a limited sort of cover like smoke in the air. I can't recall what the liquid term is. I thought it was turgidity, but I'm wrong.

For concealment it's best just to use a % fraction and get it over with. It could be 1-100% or just 0, 50, and 100 for total concealment (i.e. invisible). just apply the fraction to the standard total sighting distance (e.g. 500 yards). Distances shorter than the limit (say under 250 for 50%) aren't affected enough to make a difference.

In D&D concealment is normally simplified to sight length within the medium. So maybe 5' Wall of Fog, maybe 20' for natural fog. It depends on what you want to include.

 

[garrowolf]

This only covers things that light is not directed at or is back lit or reflective or at high contrast with the background. Those don't require a perception test. I combined it with my weapon's ranges for easier use and for use in the combat system as well. This is what I have now:

Minimal Light (+20) Short Range (120 ft) indoors at night

Partial Light (+15) Medium Range (240 ft) Overcast rural area

Faint Light (+10) Longbow Range (540 ft) Moon Lit Night, Low Tech Town at night

Glare (+20) Short Range (120 ft) Bright light at night

Light Fog (+10) Longbow Range (540 ft) Light Smoke/Fog/Rain

Heavy Fog (+15) Medium Range (240 ft) Heavy Smoke/Fog/Rain


Concealment will add another set of penalties as well. Someone with nightvision would see things as faint light even though they are in minimal light. Total darkness doesn't allow for vision base perception checks, only hearing or touch based.