Anyway, doing a try on fixing vision

Detection and Perception

Dungeons can contain a wide variety of hazards, rewards, and other targets of interest. Typically a target can be in one of four states

• Undetected: the observer is not aware of its existence and cannot deliberately interact with it.
• Detected: the observer knows the target exists, but not where it is. Interacting with it requires targeting an area and hoping the target is in it.
• Located: the observer knows the target exists, and where it is, but cannot see it. Interacting with or attacking the target is generally at disadvantage.
• Visible: the observer knows the target exists, and where it is, and can see it.

Vision and Light

The most fundamental tasks of adventuring--noticing danger, finding hidden objects, hitting an enemy in combat, and targeting a spell, to name just a few--rely heavily on a character's ability to see. Darkness and other effects that obscure vision can prove a significant hindrance.

For any given observer, a given target might be heavily or lightly obscured.

A heavily obscured target cannot be seen. The most common causes of this are darkness and an opaque object or effect entirely between the observer and the target. Abilities that require seeing the target cannot be used on heavily obscured targets. Attacks on heavily obscured targets are at disadvantage. Ability checks to see a heavily obscured object automatically fail. Unless otherwise specified, if an effect states that it causes an area to be heavily obscured, that area is also opaque.

A lightly obscured target can be seen, but not clearly. The most common causes of this are dim light, being partly behind an opaque creature, object, or effect, and being behind something partially transparent. Ability checks to see a lightly obscured target are made at disadvantage.

The presence or absence of light in an environment creates three categories of illumination: bright light, dim light, and darkness.

Bright light lets most creatures see normally. Even gloomy days provide bright light, as do torches, lanterns, fires, and other sources of illumination within a specific radius.

Dim light, also called shadows, lightly obscures targets within its area. An area of dim light is usually a boundary between a source of bright light, such as a torch, and surrounding darkness. The soft light of twilight and dawn also counts as dim light. A particularly brilliant full moon might bathe the land in dim light.

Darkness heavily obscures targets within its area. Characters face darkness outdoors at night (even most moonlit nights), within the confines of an unlit dungeon or a subterranean vault, or in an area of magical darkness.

Blinded (Condition)

If a creature is blinded, it treats all targets as heavily obscured.

Blindsight

A creature with blindsight can perceive its surroundings without relying on sight, within a specific radius. Creatures without eyes, such as oozes, and creatures with echolocation or heightened senses, such as bats and true dragons, have this sense.  Within this radius, the creature ignores obscurement from causes other than opaque creatures and objects.

Darkvision

A creature with darkvision ignores obscurement due to dim light, and treats darkness as dim light.

Invisibility

An invisible creature is heavily obscured against any creature using normal vision or darkvision.

Truesight

A creature with truesight ignores obscurement due to darkness, dim light, illusions, or invisibility.

Hiding

A creature may wish to avoid detection. How this works depends on what potential observers already know

• If the creature is unknown or known, a successful stealth check allows remaining in that state.
• If the creature is located, a successful stealth check allows reducing that to known as long as have a place you can move to (your prior location remains known).
• If an unknown creature takes actions that reveal its presence, it becomes known.
• If an unknown or known creature takes actions that reveal its location, it becomes noticed.
• If a creature has no concealment against an observer, or a located creature has only partial concealment, it becomes seen.