Questions about texturing. (Fallout 4)

Actually, straight to the point.
The problem with normal map at the opening of the original it is clearly lighter than those making "CrazyBump" but there is still okay there's a way it lighten in Photoshop "Ctrl + L" output values make somewhere such [128] _____________________ [255]
is stored in the format "3dc "with mip map generation.
The texture itself is saved in dxt1 without an alpha channel.
In the game itself, the texture under lighting or when viewed from different angles is partially black.