Use the Magic Eraser tool

The Magic Eraser tool changes all similar pixels when you drag within a photo. If you’re working in a layer with locked transparency, the pixels change to the background color; otherwise, the pixels are erased to transparency. You can choose to erase contiguous pixels only, or all similar pixels on the current layer.

Original image (left), and after erasing the clouds (right)

  1. In the Layers palette, select the layer containing the areas you want to erase.
    Note: If you select the Background, it automatically becomes a layer when you use the Magic Eraser.
  2. Select the Magic Eraser tool  in the toolbox. (If you don’t see it in the toolbox, select either the Eraser tool  or the Background Eraser tool , and then click the Magic Eraser tool icon in the options bar.)
  3. Set options in the options bar, as desired, and then click the area of the layer you want to erase.

    You can set any of the following Magic Eraser tool options:

    Tolerance
    Defines the range of colors that will be erased. A low tolerance erases pixels within a range of color values very similar to the pixel you click. A high tolerance erases pixels within a broader range.

    Anti‑alias
    Smooths the edges of the area you erase, making the edge look more natural.

    Contiguous
    Erases only pixels that are adjacent to the one you click. Deselect this option to erase all similar pixels in the image.

    All Layers
    Samples the erased color using combined data from all visible layers. Deselect the option if you want to erase only the pixels on the active layer.

    Opacity
    Defines the strength of the erasure. An opacity of 100% erases pixels to complete transparency on a layer and to the background color on a locked layer. A lower opacity erases pixels to partial transparency on a layer and paints partially with the background color on a locked layer.

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