Curves layers are one of the most misunderstood, yet more powerful adjustments you can make. Our images are all made up of pixels, which each have values for color and luminosity. With Curves adjustments, we can remap the pixels’ values for these, changing them to be brighter or darker, or changing their color.  In Skylum Software’s Luminar you can add multiple curves filters, and make each layer target very specific parts of your image.  This will give your images more depth, dimension, and beautiful color.

Add Luminosity and Color Curves

Because the Curves adjustment can affect both color and contrast, I prefer to work on one of these at a time. This way if I want to shift the image to have brighter highlights, I don’t also shift its colors.

Luminosity Curve

  • Create a New adjustment layer, then click the “Add Filter” button and select “Curves”.
  • Change the layer blend mode to Luminosity, now the Curves adjustment will only affect the luminance of the image, not the color.
  • Click on the straight line, and drag your cursor up or down to make changes. Here I added two separate curves filters, one to adjust highlights, and one to adjust shadows.  By brightening the highlights and deepening the shadows, this gives the image more depth, making it feel more three-dimensional like you can walk right into the scene. But, because we are using the Luminosity blend mode, only the tones are changed while the color still stays true.

Color Curve

Each pixel in an image also has Red, Green, and Blue values, curves can be used to remap these colors. On the Curves panel, you will see circles which correspond to each color, with the white one being the tone curve. Click any circle to adjust the curve for only that color. Dragging up will move the color more towards the pure form of it, dragging down will shift the color towards its complementary color. For example, dragging up on the red curve will make the reds redder, but dragging down will make them more cyan. Blue is paired with yellow, and green is paired with magenta. Because you can also select where along the curve you drag, you can choose to adjust only certain tonal ranges of the color, like deep blues or bright greens.

  • Create a New adjustment layer, then click the “Add Filter” button and select “Curves”.
  • Change the layer blend mode to “Color,” now the “Curves” adjustment will only affect the color of the image, not the luminance.
  • For this image I adjusted the red highlights to increase the saturation, adding a downward curve on the blue curve to pull this color out of the plants and desert sand, which replaces the blues with yellows.

Finishing Up

With my basic adjustments and two curves layers in place, you can see the change in both tone and color throughout the image is already pretty dramatic.  At this point, you can continue making adjustments in Luminar by adding more filters, or apply what you have done and return to your image in Lightroom or Photoshop.

You can certainly achieve similar effects in other programs, I use Luminar because its fast, inexpensive, and fits seamlessly into my Lightroom-based workflow.  One of the main reasons I started using it was this ability to have multiple curves or other adjustment layers, this gives you a remarkable amount of control for very specific improvements on very specific parts of your images.  Remember, every image is started in your imagination, created in your camera, but finished in the digital darkroom.  Using a tool like these curves layers helps you make the photo in your imagination a reality.


Like this article? Follow this link to read more of my photo tips and techniques. Jason’s Articles at Photofocus