My previous GIMP tutorial looked at how to create a color splash effect with an alpha channel; but today I’m going to use a layer mask to produce similar results. Read on to see how.
1. Prepare the image in GIMP 2.8
Save the image from Pixabay via the link above as a 1920×1280 image, and open it in the GIMP application by going to File > Open, or hitting CTRL+O on Windows. You can also drag and drop the image in the program.
Duplicate the image by going to Layer > Duplicate Layer or by hitting CTRL+SHIFT+D on Windows. Optionally, you may right-click your layer in the Layers dialog to find that option.
Rename your layers for clarity by right-clicking each of them and selecting Edit Layer Attributes. Let’s rename the layer at the bottom of the stack containing the base image as “original-image” and the duplicated layer on top as “duplicate-mask”.
2. Adjust the colors
Click on the eye icon of the duplicate-mask layer to make it invisible. At this point, only the original-image is showing.
Click on the original-image layer to activate it and go to Colors > Levels. We’ll be making the red color stand out in our final image, so we need to work on it in advance to make it pop out more.
In the Levels tool, select the Red channel. Under Input Levels, change the value of Midtones to 1.20 or enter that value manually in the numeric text box in the middle. Leave the Shadows and Highlights at 0 and 255 respectively, but set the Output Levels between 10 and 255.
Re-enable the top layer by toggling its visibility, and go to Colors > Desaturate.
The default option is usually Lightness, but here we want to choose the shade of gray based on Luminosity.
3. Add a Layer Mask
Still with the top layer selected, go to Layer > Mask > Add Layer Mask.
Leave the default option White (full opacity) selected and click the Add button.
4. Paint on the Layer
Go to Tools > Paint Tools > Paintbrush. This selects the Paintbrush tool (P) with which we’re going to paint areas of the image we want the color to show through (from the original-image layer below).
In the Brushes dialog, which you can access by hitting CTRL+SHIFT+B on Windows, select the brush with Hardness 050.
In the Paintbrush tool options, which you can access by going to Windows > Dockable Dialogs > Tool Options, increase the size of the brush to 30.00.
Zoom into the image at 200%.
Make sure you have black as your foreground color in the Color dialog. What you paint in black will disappear to show the colored layer below it, and what you paint in white will cause anything that disappeared previously to show again.
Paint the batter so that his body, outfit and the bat gain back their colors.
5. Enhancing the layer mask
Once you are done painting on the batter, right-click the top layer and select Show Layer Mask.
Rectify any imperfection you spot by using black or white paint as appropriate. You may notice holes in your painting indicating parts you missed with the brush, for instance, or traces of paint outside your target shape.
Right-click the layer again and uncheck Show Layer Mask to view your final image with the effect.
And that’s it!
Don’t forget to save your work as an XCF file and export it once you’re done. As we’ve seen it, Layer Masks serve to modify the opacity (transparency) of the layer they belong to, and they’re excellent tools to create color splash effects in GIMP.
Here is another interesting color splash effect I made in GIMP using the same technique with a layer mask and the paintbrush tool.
Here, I focused on the basketball (in its original color), whereas the model and the background remain desaturated (black and white).
Leave your questions and share your own color splash effects in the comment section below!