[HELP] Fix black levels

[Selur]

No, clue what you want to do exactly, so there's what usually comes to mind (assuming your source if flagged properly):

• use Levels with 'luma only' (or with 'Use RGB' depending on your preference)
  
• use a color matrix or LUT
  
• use Smooth Levels
  
• use Limiter if you want to 'cut off' a range
  

Depending on your source, stuff like 'Auto white', 'Retinex' or 'Grayworld' might also work.

Cu Selur

Ps.: from the green part I guess that you only want to adjust the luma and not all channels.