TUTORIAL:  Sky Replacement using Photoshop CS

Step One:

Open the image in Photoshop and unlock the background layer by double clicking on it in the layer palette.

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Step Two:

Select the Magic Wand tool and change the tolerance to a value of 10-20. Select a few pieces of the clouds and then go to Select > Similar.

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Step Three:

Select the Lasso tool and subtract from selection from the toolbar. Draw a box around the areas you want to subtract.

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Step Four:

Once the old sky is selected, the backspace button is used to delete the selection. The new sky image is opened and copied into the original image. The new layer is then dragged behind the background layer and positioned accordingly.

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