Use Photoshop to Swap Skies from One Shot to Another: It's Easy!
In Photoshop, You Can Mix and Match Skies to Banish Blah-Sky Syndrome!
I’d be a rich man if I had a buck for every time I’ve stumbled upon a great landscape scene only to mutter to myself, "What a horrible sky." There’s something entirely deflating about finding an interesting foreground scene with a sky the color of aged Cool Whip hanging over it. And then, of course, there are the times when a vivid sky show suddenly erupts and there isn’t a foreground worth shooting to be found.
In the pre-digital days, unless you had lots of time to wait for a change in the weather (or you were a very clever darkroom technician), you were pretty much stuck with the sky you were dealt. Image-editing programs like Photoshop or Photoshop Elements, however, have made it easy to mix and match skies from one scene to another - pasting an interesting sky in place of a boring one, or adding a powerful foreground to an already flamboyant sky.
Because appealing skies and pretty scenes seem to coordinate with one another so rarely, it's a good idea to start a library of "sky only" images that you can draw upon later. I find myself constantly shooting pictures of just sky - whether it’s a parade of puffy white clouds or a full-tilt sunset. I keep the images in an album in my iPhoto library simply entitled "Great Skies." Then whenever I find a shot that needs a quick sky transfusion, I scroll through the thumbnails for a sky that has approximately the right coloring or look for that scene.
Replacing a sky is pretty simple, you’ll need just two things:
1. An image that needs a new sky and
2. A better sky image to replace it with.
Utah landscape with boring sky
Sunset shot in Titusville, Florida
Where to Begin
Step One: Begin by choosing an original scene that has a simple and clear separation between sky and foreground. For this example, I chose an interesting rock formation shot near the Valley of the Gods in southern Utah. Daylight was fading quickly when I shot the scene and although the sky wasn’t entirely bland, I knew I had better skies that would improve the shot.
Step Two: Using your selection tools, select the sky area only, being careful to find a precise line between foreground and sky. Unless your selection skills are exceedingly good, using scenes with complex sky-foreground borders can be tricky. Bare trees with a lot of intricate branches and twigs are a lot more difficult to separate from the sky area than a thick row of pines, for example.
I prefer to use the “Magic Wand” selection tool in Photoshop and Photoshop Elements for this kind of work because it is very fast at selecting large areas of sky. Occasionally if the sky is a very even tone, the Magic Wand will select the sky in a single click.
Tip: To make the line between sky and foreground seem more natural, feather the selection (Selection>Feather) by a few pixels (one to three pixels works well). Also, if you find that you are getting a slight “halo” edge around your foreground, try expanding the sky selection (Selection>Modify>Expand) by a few pixels so that it bleeds very slightly into the foreground.
Once you’ve carefully selected the sky, you can hit “delete” to remove the existing sky and see your selection better (this step is optional, however, since you can paste right over the existing sky).
Utah landscape with sky removed
Next: Open the image of the sky that you want to use as your replacement sky and then, using the select all command (Command A on a Mac, Alt A on Windows), select the entire image. In this case I chose a sunset that I shot over the Indian River in Florida. Next, use the copy command to copy the sky image into memory.
Return to the original image and click anywhere in the selected sky area then use the paste into (Edit>Paste Into) command to place your new sky into that image.
Once youve pasted the new sky, you can then use the Move tool to move slide it around until you find a pleasing composition. I find this is the most creative part of the exercise - shifting the sky around until it fits naturally into the scene.
Incidentally, if your new sky doesnt fit into the sky area of the original scene exactly, or if you want to elongate or change the shape of clouds a bit, you can use the transform tool (Image>Transform>Free Transform) to stretch (or shrink) your sky to its new home. Some distortion will occur if you stretch the sky too much, but its unlikely to be detectable.
Finally, save the image in its layered form (leaving the layers open) so you can modify it later if you choose to make additional changes. Then, once youre satisfied with the image, flatten it to merge the layers and give it a new name. By giving the flattened image a different name, you will have your layered version available for future tinkering but also have a final image that you cant accidentally disturb.
Next time youre out shooting and find a great scene that desperately needs a better sky, or find a sky in need of a new foreground home, keep shooting - you can create the final image in the computer.