How To 

How To Create A Water Displacement Map In Photoshop

Displacement maps are grayscale images saved as .psd files that you can use to distort a flat image to conform to a texture. While often used to map images onto fabric or surfaces that have an implied “3D” depth, we’re going to use color channels to make a map that will allow an image to imitate the distortion caused by the rippling of waves. This is how we’ll do it.

1. Create a new Photoshop document.
Since we want to apply this to as many image types as possible, we’re going to create a document that is very tall. We’ll set the dimensions to 1200 x 2000 - most images in portrait or landscape aspect ratios should be able to fit within these confines.

2. Apply a fill to the background layer.
We’ll begin by adding a fill by hitting “Edit > Fill..”. A dialog box will appear - from here, we’ll set the Contents to “Black”, the Mode to “Normal” and leave the Opacity level at 100%. With everything ready, we’ll hit “OK”.

3. Add a Noise filter to the background layer.
With the newly filled layer selected, we’ll hit “Filter > Noise > Add Noise…” to open the “Add Noise” dialog box.

4. Adjust the “Add Noise” parameters.
We want as much noise as possible to give us more variance in our final displacement map, so we’ll max out the Amount at 400%. We’ll also want the noise uniformly distributed so we’ll go ahead and check the “Uniform” option. With everything ready, we’ll hit “OK”.

5. Add a Gaussian Blur to the background layer.
With our noise added, we’ll keep the background layer selected and hit “Filter > Blur > Gaussian Noise…” to open the “Gaussian Blur” dialog box.

6. Adjust the Gaussian Blur parameters.
Without a blur applied, our final displacement map will contain hard, chunky edges that won’t accurately replicate the patterns of rippling waves. To fix this, we’ll set the blur Radius to a fairly low setting (1.5 pixels) so that we can soften the edges of our map without losing detail.

7. Select the image’s red channel and add an Emboss filter.
For this step, we’ll begin by opening the “Channels” tab in the Layers panel. From there, we’ll select the image’s “Red” channel and open the Emboss filter by hitting “Filter > Stylize > Emboss…”. A dialog box will open.

8. Adjust the red channel’s Emboss parameters.
What we’re doing here is differentiating between the RGB channels so that we can apply their pixel information to the distortions of our displacement map. We want the emboss to be applied as strongly as possible without displacing pixels, so we’ll keep the Height at 1 pixel and the Amount at 500%. We’re aiming for each channel to drift away from each other, so each channel will get its own Angle setting - this one will be 180°. With everything good to go, we’ll click “OK”.

9. Apply an Emboss filter to the green channel and adjust its parameters.
We’re now going to repeat the last two steps for the green channel. We’ll first select it under the Channels tab, then open the Emboss filter as we did before. The settings here will be exactly the same as last time, with the key exception of the Angle, which we’ll set to 90°. We’ll then hit “OK”. After this step is completed. The red and green channels will shift in opposite directions while the blue channel will remain exactly where it was before.

10. Open the “Perspective” transform mode.
With our emboss set, we’ll return to the Layers tab and select our original image. Make sure to click the “lock” icon here to unlock the layer so that we can apply a transformation. We’ll now be able to open the Perspective mode by hitting “Edit > Transform > Perspective”.

11. Warp the map to replicate a water surface.
The goal here is to stretch the edges of the image so that it begins to look like we’re looking down on it from above. To do this, you’re going to have to hit Cmd and “-“ (Ctrl and “-“ in Windows) a few times to zoom the image out to around 4%. Then, you’ll stretch the bottom handles to the far corners of the screen to warp the image.

12. Save your displacement map.
The image should now replicate the perspective and ripples of a large body of water. To save this as a displacement map for later use, go to “File > Save as…” and save this project as a .psd file.