What affects how fast you are spotted by enemies?

Question

From Skyrim and Oblivion that brightness and the weight of your armor have a big influence on how quickly you were spotted by an enemy or a mere house inhabitant - especially while you were sneaking.

However, in Fallout 4 I did not notice much consistency during sneaking. Examples:

1. My armor's weight was often different → no difference recognized.
2. Light source of the surrounding was often different → no difference recognized.
3. My crucial experience which led me to create this question: The Torchlight, which is activatable with long pressing of TAB, seems to have no influence at all. In some cases there was just a corridor, I had the torchlight turned on, but the enemies (mainly raiders or looters, humans by any means with some basic intelligence) didn't find or see me although they recognized that someone entered the area.

The only thing which clearly seems to have an influence is opening fire: Without a silencer the enemies are able to spot you much more quickly. That's the reason why I primarily use a silenced pistol.

So, those are my experiences. Might any friend of sneaking out there have facts for those experiences? Does the companion also take a role here maybe? Or am I really true and there wasn't much effort put into the sneaking/spotting system, what I can't imagine?

Answer 1

Your ability to sneak is affected by 8 different factors:

• Equipment weight: Although you said there was no difference, there is a difference if you walk. The heavier the armor or weapon, the further you'll be heard if you move. However, if you stand still, your armor weight won't affect you at all.
• Light sources: Light sources also influence your ability to sneak heavily. However, this only affects you if an enemy has a clear LoS on you. If you are in a lit room with no enemy being able to see inside, the light does not affect you at all.
• Your agility skill: The more agility you have, the more difficult you become to spot when sneaking. This affects you in both moving and not moving.
• Perception of the enemy: This is also a huge factor which both affects you moving or not moving.
• Distance: Obviously, the further the enemy is away, the hard it will be for him to spot you.
• Any form of contact: If you touch an enemy, he will immediately spot you.
• Loud Weapons: Any form of attacking an enemy will make them spot you. However, silenced pistols, melee weapons and grenades/mines will not break your stealth, although it will cause the caution alert if you do not kill them in one hit. Grenades always cause caution alert if there are any alive enemies in the area.
• Special gear: There are several modifications like shadowed which can improve your ability to sneak. Also, gear obtained from legendary enemies can have a stealth-improving effect on you.

Your pip-boy (includes the torchlight) do not affect stealth at all as you already found out. You can also listen to radio while sneaking and nobody will notice.