do you want to play with Derpswen but dont want the moody lighting, and the need to bring torches always into caves?

read below for two things you can do to disable this:
go to options > video settings > quality > and turn "custom colors" to off.
however, this also does affect the colors of spruce leaves, birch leaves, custom colored lava and the custom water color.

if you wish to play without the custom lighting but have the other features, in the zip archive go into assets > minecraft > optifine > and delete the lightmap folder.

maybe you want the lighting but not the colormaps?
delete the "optifine > colormap" folder.

if you wish to access the vanilla colormaps of the grass, oak leaves, things such as these, go into assets > minecraft > textures > colormap > and delete the grass.png and foliage.png files.

make sure you get them correct - lightmap is lighting, colormap is coloring