Light
3	Outdoors, sun up, no clouds
2	Outdoors, sun up, clouds
1	Outdoors, moon(s) up, no clouds
0	Outdoors, moons(s) up, clouds
-1	Outdoors, no moons, no sun, clouds
-2	


Sky light sources
Stars: 			+1
Sun/Just below horizon	+1
Sun/At horizon		+2
Sun/Above horizon	+3
Moon(s)			+1, no effect if sun illuminates at all 

Sky dark sources
Light Clouds:		-1
Normal Clouds: 		-2
Heavy Clouds: 		-3
Supernatural Clouds: 	-4

Light Sources
Weak:	Torch/Lamp: +1	
Strong:	Light spell: +2

Darkness Sources
Weak:	Darkness spell: -1
Strong:	Sinister Darkness: -2

Sun	Moon(s)	Stars	No	Light	Medium	Heavy	Super
Above	1 to 3	Yes	4	3	2	1	0
Above	0	Yes	4	3	2	1	0
At	1 to 3	Yes	3	2	1	0	0
At	0	Yes	3	2	1	0	0
JB	1 to 3	Yes	2	1	0	0	0
JB	0	Yes	2	1	0	0	0
Below	1 to 3	Yes	2	1	0	0	0
Below	0	Yes	1	0	0	0	0
Below	0	No	0	0	0	0	0	(Indoors)

The strongest light source and darkness source add to the light level.
Light Source cannot bring the illumination above it's bonus and Darkness
Source cannot drop it below it's level. (Weak: +1 / -1, Strong: +2 / -2)