We want to replace the dull gray clouds with a nice blue sky.
In this first method we will create the sky using a gradient.
To use a sky from another picture, skip to Image 6.
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1. Add a blank layer and apply a Layers Mask to it.
2. Select the foreground (non-sky). In some cases it is easier to select the sky and invert the selection.
3. Activate the mask and fill the selection with black.
4. Important! Delete the selection (Ctrl-D).
Now to use a gradient to create a natural-looking sky ranging from light blue at the bottom to dark blue at the top ...
5. Set the Foreground and Background color chips (bottom of toolbar) to light and dark blue.
6. In the Gradient Editor select the Foreground to Background preset, and on the tool options bar choose Linear Gradient.
7. Click the layer's thumbnail to activate the layer, and draw the gradient vertically upwards. Because of the mask the gradient does not cover the foreground.
The degree of the light-to-dark transition depends on the gradient's start and end points, so you might have to redraw the gradient several times until it looks right. You can redraw over the existing gradient; no need to start from scratch.
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You can add clouds using photo-realistic cloud brushes. Here I used a variety of these brushes. You don't "paint" as you normally do with the Brush tool. Instead just click once to add the cloud.
There are 2 options: 1. Paint the clouds directly on the sky layer as I did with the bottom cloud. Portions of the cloud over the foreground are obscured by the mask. However this is permanent, so any clouds added cannot be removed, or will be removed if you want to draw a different gradient.
2. Ctrl-click the sky layer's mask to select the foreground. Invert the selection. Add a blank layer above the sky layer. Paint the clouds. Portions of the cloud which would be over the foreground are obscured because only the sky is selected.
An excellent set of cloud brushes is the Return to Eden set which I used in this example. You can also do an Internet search for "Photoshop clouds brush" or similar.
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If the Gradient layer has the default Normal blending mode (as in the previous slides) the gradient will be solid and wipe out any existing clouds.
Other blending modes preserve clouds and existing light variations. Here are some examples using the same light blue to dark blue gradient.
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and more examples
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In this example we want to replace the sky with a sky from another picture.
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1. Open the sky picture and select it (Select > All).
2. Copy the sky picture to the clipboard (Edit > Copy).
3. Open the destination picture and paste the new sky from the clipboard (Edit > Paste). This creates the sky on a new layer. Resize and reposition the layer as necessary to cover the original sky.
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1. Apply a Layers Mask to the sky layer.
2. Temporarily turn off the visibility of the sky layer.
3. Activate the picture layer and use the various selection tools to select the foreground. In some cases it is easier to select the sky and invert the selection.
4. Turn on the visibility of the sky layer, activate the mask, and fill the selection (the foreground) with black.