ClassicLight modifies light computation in Minecraft 1.8+ to resemble that of earlier versions, like 1.7.3. As a bonus, it adds support for tinting of blocklight and a few other features.
And to demonstrate that it is indeed different than just turning off Smooth Lighting, here’s a picture of ClassicLight with Smooth lighting on
Adjusting the config:
This mod adds a config. You can find it in .minecraft/config/mod_classicLight.cfg. Here’s what the keys do:
All of these are 255 by default. Change the values to adjust how the lighting tints. For example, set red and green to “210” for a nice blue tint. Try to keep as much “white” in your colors as possible, or else things will look weird (in particular 0, 0, 255 looks terrible, as well as the other super intense colors)
To toggle the void fog remover, set “voidFog” to false.