Hard Light combines the effects of Multiply and Screen based on the brightness of the blending layer. Colors lighter than 50% gray brighten the image, while colors darker than 50% gray darken it, creating a stronger, more contrast-heavy effect than Soft Light.
The Math
Hard Light uses the brightness of the blending layer to determine whether to lighten or darken the base. Colors brighter than 50% gray use a Screen-like effect, while colors darker than 50% gray use a Multiply-like effect.
At exactly 50% gray, the effect is neutral and has virtually no impact on the base layer.
Core Rules of Hard Light
50% gray is neutral: Painting with 50% gray has virtually no effect on the layer underneath.
Light colors brighten: Colors above 50% brightness use a Screen-like effect, making the base lighter and more luminous.
Dark colors darken: Colors below 50% brightness use a Multiply-like effect, deepening the shadows.
Strong contrast: Hard Light produces a much more intense result than Soft Light, making it useful when you want lighting or color changes to have more punch.
Hard Light vs. Overlay
Hard Light and Overlay use the same basic idea but determine the effect from different layers.
Overlay: The base layer determines whether the result behaves more like Multiply or Screen.
Hard Light: The blending layer determines whether the result behaves more like Multiply or Screen.
This makes Hard Light more strongly influenced by the colors you paint with, while Overlay responds more strongly to the artwork underneath.
When to Use It
Strong lighting: Paint with bright, saturated colors or warm gradients to create intense sunlight, environmental lighting, or dramatic highlights.
Atmospheric moods: Use a broad color wash, such as an orange-pink sunset gradient, to shift the mood or apparent lighting of an illustration. Lower the layer opacity for a more subtle effect.
High-contrast effects: Use Hard Light when you want a texture, color, or lighting pass to have more punch than Soft Light or Overlay provides.