Tutorial: 8 steps to replace a sky in Photoshop

With the recently just completed project for the Aberystwyth University Hiking club, which I discussed in full here, I decided to make a tutorial to showcase one of the skills I learnt for this project; how to replace a sky, to turn this…


…into this using Photoshop!


I was definitely inspired by the fantastic tutorial created by Nathaniel Dodson from Tutvid for sky replacements, and while the example I show here is relatively simple, he goes into far greater detail with much greater complexity. I’ve embedded the video below which is well worth a watch. Also, it’s well worth checking out his website Tutvid.com and YouTube channel if you’re into photography, web design and graphic design.

So I am starting with one of the club photos. It’s a good photo, in general with a little bit of editing in Camera Raw. However, the sky is so overexposed it has just become a white block, which doesn’t look very realistic, so ideally it needs replacing.


It’s important to remember that the sky you use as a replacement must match that of the original weather conditions, so in this case we need to do a bit of detective work! 😛
We can see that the shadows are minimal to invisible, and with a relatively low contrast between the highlights and shadows of the image, it points to a cloudy sky.

So I searched my library of photographs I have started taking to use as resources when necessary, and came across this photo of a rather cloudy sky I took while on holiday in Yorkshire this summer. With a lot of texture in it, I felt it would be a good fit for the original.


Step by Step:

1. Open the photographs up in Photoshop and for both of them, double-click on the Background layer in the Layers Palette, in order to convert it into a layer. Give the layer a name and click OK.

Screen Shot 2013-09-09 at 15.00.59

2. To remove the sky we need to select it. While there are many other selection methods discussed in the video above that are better suited to the majority of images, here we can use the Quick Wand tool from the Tools Panel as it is just a solid white block. To use the tool it is as simple as clicking in the white area to make a selection. For skies where it is a mixture of similar colour values instead of just one colour, the selection range can be altered by increasing the Tolerance values in the Control Bar.

Screen Shot 2013-09-09 at 15.01.153. To ensure the selection would not leave a pixel or two of white around the edge of the hillside, I went to Select > Modify > Expand, and chose 3 pixels as the value.

Screen Shot 2013-09-09 at 15.02.06

4. With a selection now created, it is time to remove it’s contents. While I could just press the Backspace key, I have learnt it is better to edit an image in a non-destructive manner, as it keeps the original intact. So instead I added a Layer Mask. The button can be found at the bottom of the Layers Palette.

Screen Shot 2013-09-09 at 15.22.43

However, if I just click it, the sky remains and everything else disappears… not what was desired. So instead you can press the alt or option key which inverts the layer mask, giving us the desired result.

Screen Shot 2013-09-09 at 15.02.23

5. Now swap to the cloud photograph, choose the Move Tool from the Tools Panel and drag the sky across onto our landscape image to reveal it and drop the new sky into position. You can see from the image below how I have done it, and it doesn’t need to be overly precise.

Screen Shot 2013-09-09 at 15.30.03

You can also enter Free Transform mode (Cmd/Ctrl + T) to re-size the new sky to fit the area you need. Pressing the Shift key while re-sizing keeps the image in proportion.

Screen Shot 2013-09-09 at 15.29.18

6. As you can now see, I need to swap the layers around, so the ‘Cloudy Sky’ layer is behind the ‘Hillside’ layer. To do this, just click and drag the top layer below the other one and drop it into place.

Screen Shot 2013-09-09 at 15.33.53

7. While the sky looks alright in that position, it does not have the correct perspective, as the clouds in the image were taken by me pointing a camera directly up into the sky, instead of into the distance.

To correct that, I entered the Free Transform Mode (Cmd/Ctrl + T). Instead of just dragging the corner squares, press the Cmd or Ctrl key while dragging and you will see you can ‘warp’ the image as I have done below.

Screen Shot 2013-09-09 at 15.46.53

It needs some careful adjusting to create a realistic effect, and you can also select the Move Tool to move the image around if you would rather display another part of the sky.

Screen Shot 2013-09-09 at 15.47.17

8. Looking at the new sky in position, I decided to decrease the contrast a touch to match it to the rest of the image. To do this, I selected the ‘Cloudy Sky’ layer, clicked on the Adjustment Layer button at the base of the Layers Palette, and selected Curves. I clicked on the graph to add a couple of points, and dragged them upwards to lighten the shadows and the highlights. This gave me the desired effect I wanted.

Screen Shot 2013-09-09 at 15.50.40 Screen Shot 2013-09-09 at 15.53.16

If you are continuing to add layers and edit beyond this point, it is worthwhile clipping the Curves adjustment layer to the ‘Cloudy Sky’ layer, so Photoshop knows the adjustment layer is only wanted to work on that one layer, rather than all the layers below. To make this happen, click the Clip button in the Adjustment Panel.

Screen Shot 2013-09-09 at 15.53.26

And that, is that! Hopefully you should have a successful sky replacement. Let me know if this tutorial works for you, or if there’s anything you think needs improving in my style of presenting tutorials.