Correct colors using Tone Curve tool in Lightroom

There are different tools in Photoshop and Lightroom that will help you enhance your photo color cast, exposure and tonality. One particular tool available in both applications is the levels tool in Photoshop or the Tone Curve in Lightroom. Once you adjust Shadows and Highlights, the Tone Curve adjustment should be your next go-to tool if you have any color cast like the yellow cast in our starting photo below (fig.1.)

Fig.1. Notice the yellow color cast. Although this could be fixed in WB Temperature adjustment slider, we will be systematically eliminating Green, Blue, and Red channels cast using the Tone Curve tool in Adobe Lightroom.

The Tone Curve tool in Lightroom is very much similar to Levels in Photoshop. It corrects the tonal range and the color balance. The Tone Curve tool uses a histogram to show you visual representation of the tonal range in your image. On a histogram, the right side represents total white with no details. If the histogram is leaned to the left side, it means that you have more dark pixels in your photo and your image might be underexposed. How does the Levels tool work?

Before you make any adjustments to exposure, have a close look at your photo to see if it has a color cast. Fig.1. definitely has a yellow color cast affecting the whole pixels. One way to find color casts in your photos is to look at an area that should be white and see if it has a tint. A color cast will vary depending on the light you shot under; it could be green, magenta, blue, yellow, orange, or anything in between.

If you have a photo needing color cast correction, like the one above, then do the following:

  • Press "D" to go to the Develop module in Lightroom.
  • Click on the twisty of the Tone Curve tool directly below the Basic panel on the right hand side.
  • Make sure your tool looks like Fig.2. and not like Fig.3. If it does click that lower small buttom to toggle between its modes.
Fig.2. Tone Curve panel

Fig.2. Tone Curve panel

Fig.3. Not the one we will be using

Fig.3. Not the one we will be using

  • Click on the drop down box below the histogram that says RGB. Select RED and bring the top right point to the left  (Fig.4.)  Next select the GREEN channel and do the same (Fig.5.), and finally the BLUE channel (FIG.6.) By sliding the top right point inward to the histogram, you are neutralizing the color cast. Don’t be alarmed at the strange colors you are having. They will work out in the end.
  • Once you have adjusted the individual color correction in all three colors, you can now adjust the exposure and contrast like you always do by select the RGB channel. 

Fig.4. Adjust the RED channel

Fig.5. Adjust the GREEN channel

Fig.6. Adjust the BLUE channel

Always remember that in any Photoshop or Lightroom adjustment, don't overdo your sliders. Smaller  adjustments always work better so do small changes first and add more like the salt and pepper on your food.

Fig.7. the before and after. Notice the white wall...