This block of dirt was exposed in a lit room during daylight, but the light level while standing at the block shows as zero.
Smooth lighting is disabled in these pictures. Turning on smooth lighting does allow a small amount of light into the adjacent blocks, but it's very little - just the smoothed light; the base light level.is still zero.
No mods were used in this world.
This block of dirt was exposed in a lit room during daylight, but the light level while standing at the block shows as zero.