Levels

Overview

Adjusts tonal separation in an image or mask. It can make dark areas darker and bright areas brighter, or keep values from reaching full black and white.

The default OKLCH-L adjusts perceived brightness naturally. Switch mode when you need direct RGB values, alpha-only adjustment, or HSV value.

Usage tips

• The five values have distinct roles: input_black/white defines what becomes black/white and tightens the range; gamma below 1 darkens midtones while a value above 1 brightens them; output_black/white limits how far black/white can go.
• It is ideal for noise → mask adjustment. Applying input_black/white to noise_generate output controls patch area and density intuitively, providing a softer middle ground than threshold.
• Choose between this and tone_curve by shape: this node is faster for linear range adjustment, while a curve is better for an S-shape or other custom response.

Common pitfalls

• Tones disappear from over-adjustment: bringing input_black and input_white too close approaches a binary result. Keep space between them unless that is intentional.
• Input Black exceeds Input White: evaluation swaps them into ascending order and warns on both parameters. Reversing Output Black and Output White remains an intentional output inversion.
• Colors look muddy: RGB mode also changes saturation. Keep the default OKLCH-L when only luminance should change.
• The mask edge becomes hazy: raising output in Alpha mode makes the entire mask translucent. Use the input controls when the goal is a crisper edge.

Examples

• Tighten character shadows with OKLCH-L so the pixel shapes read more clearly.
• Use Alpha to make a translucent mask crisp.
• Use output_black and output_white for a soft mask without crushed black or blown white.

Related nodes

• tone_curve — a freely shaped tonal curve
• auto_levels — adjust the range automatically
• threshold — complete binarization
• brightness — simple brightness increase/decrease