How Photoshop Eyedropper Samples Layer Colors

The Eyedropper Tool in Adobe Photoshop samples color values directly from canvas pixels based on user-defined sample settings in the Options bar. By adjusting the tool's sample scope and sample size, users can control whether the tool records the raw pixel data of a single isolated layer, a flattened composite of all visible layers, or a targeted stack, accounting for layer opacity, blending modes, and adjustment layers.

Sample Scope Settings

The core mechanism dictating how the Eyedropper interacts with the layer stack is the Sample dropdown menu located in the top Options bar. This setting determines which layers contribute pixel data to the sampled color:

  • Current Layer: The tool samples color exclusively from the currently selected layer in the Layers panel. Any overlapping layers above or underlying layers beneath are ignored. If you click on a transparent area of the active layer, the tool samples pure transparency (no color is picked), even if visual content exists on other layers at that coordinate.
  • Current & Below: The tool samples the combined visual result of the active layer and all layers situated beneath it in the stack. Layers positioned above the active layer are excluded from the calculation.
  • All Layers: The default behavior. The tool samples the final composite color displayed on the canvas, behaving as a "what you see is what you get" picker. It calculates the resulting color after processing all visible layers, opacities, and layer masks.
  • All Layers no Adjustments: The tool samples the composite of all visible layers while ignoring the color shifts introduced by non-destructive Adjustment Layers (such as Curves, Levels, or Hue/Saturation). This allows you to sample the base colors of your composition without altering your palette with temporary grading.
  • Active & Below no Adjustments: This combines the hierarchy limit of "Current & Below" with the exclusion of adjustment layers, sampling the composite up to the active layer while bypassing adjustment effects.

Sample Size Averaging

In addition to layer targeting, the Eyedropper determines color values using the Sample Size setting.

  • Point Sample: Reads the precise numerical color value of a single pixel under the cursor. This can sometimes lead to inconsistent sampling in textured or noisy images.
  • Averaged Samples (e.g., 3 by 3, 5 by 5, up to 101 by 101 Average): Calculates the arithmetic mean of pixel color values within the specified pixel radius across the selected layer scope. This smooths out grain, compression artifacts, and high-frequency color variations.

Handling Transparency and Blending Modes

When sampling across multiple layers (such as with "All Layers"), Photoshop calculates the sampled value after applying layer opacity, fill opacity, and blend modes (e.g., Multiply, Screen, Overlay). If a semi-transparent layer sits atop a colored background, the sampled value represents the mathematically blended RGB value resulting from that interaction, rather than the raw color assigned to the upper layer.