Color Correction and Color Matching With Curves
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Your choices stick across every tutorial on this device.
Color correction with Curves in Photoshop removes a color cast by balancing the red, green, and blue in your image with a Curves Adjustment Layer.
The Curves Adjustment Layer offers a lot of control and flexibility. That’s why it’s a go-to tool for color correction.
This tutorial is for beginners who want to know what each curve does to the colors, instead of guessing.
You’ll fix a red color cast by eye, then set exact black and white points with the Eyedroppers.
You’ll also use Curves for color matching, so a jet you add to a sunset sky blends right in.
The video was recorded in Photoshop 14.x, the 2013 release. Every tool it uses works the same way in the current version.
Key Takeaways
- When red, green, and blue have equal values, you get a tone with no color: black, gray, or white.
- To remove a color, add its opposite. Red pairs with cyan, green with magenta, and blue with yellow.
- Dragging a channel’s curve down doesn’t just remove that color. It adds the opposite color, so lowering the Red curve adds cyan.
- The brightest spot isn’t always the right white point. Skip specular highlights and pick the brightest area that still has detail.
- If the Color Picker only picks white, the layer mask is selected. Click the Curves Adjustment Layer icon first.
- Clip the Curves Adjustment Layer to your subject so the color match changes only that layer, not the background.
Table of contents
- What You Will Learn
- Requirements
- Curves Color Correction Keyboard Shortcuts
- How Color Works in Photoshop
- Red, Green, and Blue Make Every Color in Photoshop
- See the Color Channels in Photoshop
- Learn the Opposite Colors for Color Correction
- Color Correction With Curves in Photoshop by Eye
- Use the Curves Eyedroppers for Color Correction
- Find the Darkest Point With Threshold
- Find the Brightest Point With Threshold
- Set the Black, White, and Gray Points in Curves
- Read the Channel Curves to Fine-Tune the Color
- Color Match a Composite With Curves
- Clip a Curves Adjustment Layer to the Jet
- Pick Target Colors With Find Dark & Light Colors
- Fine-Tune the Color Match in Each Curves Channel
- Optional: Add a Yellow Highlight and Lens Flare
- Paint a Yellow Highlight With Blend If
- Add a Lens Flare in Photoshop
- Frequently Asked Questions
- Conclusion
- Related Links
What You Will Learn
- How red, green, and blue combine to make every color in Photoshop
- How to remove a color cast by editing one channel in Curves
- How to find the darkest and brightest points of an image with Threshold
- How to set black, white, and gray points with the Curves Eyedroppers
- How to match a subject to its background with Find Dark & Light Colors
- How to finish a composite with a Blend If highlight and a Lens Flare
Requirements
Before you start
- Photoshop 14.x (the 2013 release) or the current version
- The practice files below, if you want to use the same images
Practice Files
Download the tutorial files, including the RGB and CMYK color demos, and follow along step by step.
Curves Color Correction Keyboard Shortcuts
| Action | Windows | macOS |
|---|---|---|
| Place a color sampler in Threshold | Shift click | Shift click |
| Clip a layer to the layer below | Alt click between the layers | Option click between the layers |
| Split a Blend If slider | Alt drag the triangle | Option drag the triangle |
| Default colors (black and white) | D | D |
| Fill with the foreground color | Alt Backspace | Option Delete |
How Color Works in Photoshop
Before you move a single curve, it helps to know how color works in Photoshop. Then you’ll understand what each adjustment does to your image.
It’s a complex subject, but the basics are simple. You only need a few ideas to make sense of Curves.
Red, Green, and Blue Make Every Color in Photoshop
Every image in Photoshop, and on any screen, is made of only three colors: red, green, and blue.
The practice file shows this with a statue image built from three layers in a folder. One layer is red, one is green, and one is blue.
The layers use the Screen blend mode. Screen adds the colors to each other to create new colors.
Select the Red layer and move it to the right. Then move the Blue layer to the left. Now you can see that each layer holds just one color.
A gradient with nearly every color you can display on screen works the same way. It’s still just red, green, and blue.
Add an equal amount of all three colors and you get white. Take all three away and you get black.
See the Color Channels in Photoshop
You don’t need a special graphic to see this. Open any image and click the Channels panel.
You’ll find a Red channel, a Green channel, and a Blue channel. That’s what Photoshop does behind the scenes with every single image.
Now open the Info panel and hover over the image. White reads 255 in all three channels.
Hover over the grays and the red, green, and blue numbers always match. That’s how RGB creates luminance, the light and dark tones of an image.
A color cast means the image has more of one color than the others. With a red color cast, there’s more red than green or blue, so the balance isn’t right.
Hover over the colors in the gradient instead, and the numbers are all over the place. They’re not balanced.
Learn the Opposite Colors for Color Correction
To color correct images in Photoshop, you need to know the color wheel and each color’s opposite.
| Color | Opposite color |
|---|---|
| Red | Cyan |
| Green | Magenta |
| Blue | Yellow |
These opposites are the same colors as CMYK, the other color mode, which is used for printing. K stands for black.
Your color printer uses cyan, magenta, and yellow for a reason. Those inks control how much red, green, and blue light bounces off the paper.
That makes RGB an additive color mode and CMYK a subtractive color mode.
So if an image has too much red, give it more cyan to balance it. If it has too much yellow, add blue.
That one idea is the heart of color correction with Curves in Photoshop.
Note: You don’t need to memorize all of this. Knowing how it works helps you fix more complicated color problems.
The practice files also include a CMYK version of the demo. It builds the same image from cyan, magenta, yellow, and black layers set to Multiply.
Color Correction With Curves in Photoshop by Eye
Now put that knowledge to work on an image with too much red. The opposite of red is cyan, so the fix is to add cyan. In Curves, you do that by removing red.
Curves works a lot like a light switch. Drag a channel’s curve up and you add light in that color. Drag it down and you take that light away, so the image shifts toward the opposite color.
- Add a Curves Adjustment Layer so you work non-destructively.
- In the Properties panel, open the RGB dropdown and choose Red.
- Drag the curve down to remove red. The image shifts toward cyan, and the color cast starts to disappear.
- Turn the layer’s visibility off and on to compare the before and after.
- Where one end of the curve has no color information, you can also drag that end point in.
You’re eyeballing it here, so take your time. You can also adjust the other channels, or use RGB to change all the channels at once.
In short, removing red is the same as adding cyan. The result is a vast improvement, but there’s still more to fix, and eyeballing it takes time.
Use the Curves Eyedroppers for Color Correction
If you don’t want to eyeball it, use the Eyedroppers in a Curves Adjustment Layer. Each one sets a different point in the image.
| Eyedropper | What it sets |
|---|---|
| Black Point Eyedropper (black inside) | The darkest colors in the image, the black point |
| Midtone Eyedropper (gray inside) | The grays in the image, the midpoint |
| White Point Eyedropper (white inside) | The lightest colors in the image, the white point |
You could click the lightest, darkest, and gray areas by eye. The image looks a lot better, but it’s still not good.
Instead, delete that layer and add a new Curves Adjustment Layer. This time, let Photoshop tell you where the darkest and lightest points are.
Find the Darkest Point With Threshold
- Click the Background layer, the layer with the truck.
- Go to Image > Adjustments > Threshold.
- Drag the slider to the left, and everything turns white. Then drag it to the right until black sections appear. Those are the darkest points in the image.
- Hold Shift, and a little icon appears on top of the Eyedropper.
- Keep holding Shift and click a dark area. That leaves a color sampler on the darkest point.
Note: The color sampler only marks the spot, so you don’t have to remember it later. If you can remember it, click Preview to see where it is and skip the sampler. Here, it’s the part of the truck right above the wheel.
Find the Brightest Point With Threshold
- Drag the slider all the way to the right, and everything turns black.
- Drag it slowly to the left until bright points start to appear.
- Click Preview to check what those points are. Skip specular highlights. They blow out all the detail, and you want the brightest point with detail.
- Hold Shift and click the brightest area with detail. In this image, that’s the white lines painted on the ground.
- Click Cancel. Clicking OK would apply the Threshold and turn your image black and white.
Tip: You can also add a Threshold adjustment layer instead, so nothing is applied to your image. Holding Shift and clicking places the color samplers the same way, and you can delete the layer once they’re in place.
Set the Black, White, and Gray Points in Curves
- Double-click the Curves Adjustment Layer icon to bring up the Properties panel.
- Click the Black Point Eyedropper, then click the dark color sampler to set the darkest point.
- Click the White Point Eyedropper, then click the light color sampler to set the white point.
- Click the Midtone Eyedropper and click something you think should be gray.
There’s no real way to find the gray tones, so click around until you find something you like. Try the roof or the truck. Here, the roof looks pretty good.
Compare the before and after. The image looks much better.
Read the Channel Curves to Fine-Tune the Color
You could start with the Eyedroppers and skip the color theory. Knowing it, though, tells you what the Eyedroppers just did.
Open the Red channel in Curves. The curve went up, adding red to remove some of the cyan in this image.
If there’s still a little too much cyan, drag the curve up. If there’s too much red, drag it down.
Now check the Green channel. The curve was pushed down to add magenta. The original image had too much green.
Tip: Can’t remember the opposite colors? Open the Image > Mode menu. CMYK Color sits right below RGB Color, so C lines up under R, M under G, and Y under B.
In the Blue channel, you can add more blue or bring it down. Here, the result already looks good, so leave it where it is.
Color Match a Composite With Curves
Curves can also match the color cast of a subject to its background when you composite images. In this example, a jet goes into a sunset sky.
There are many ways to match colors in Photoshop. A Curves Adjustment Layer is one of the most flexible.
Clip a Curves Adjustment Layer to the Jet
- Add a new Curves Adjustment Layer above the jet layer.
- Click the clip icon in the Properties panel to clip it to the jet. You can also hold Alt (Windows) or Option (macOS) and click between the two layers.
Now the Curves adjustment affects only the jet, not the background. The background already has the colors you want, and you’re matching those colors onto the jet.
Pick Target Colors With Find Dark & Light Colors
You’ll set the jet’s target colors in Auto Options. The same options also hold hidden algorithms for easy color correction.
This sky has few true blacks, only dark reds, so you can eyeball the dark color. You can also use the Threshold method from earlier.
- Click the Curves Adjustment Layer icon in the Layers panel, not its layer mask.
- Open the Properties panel menu and choose Auto Options.
- Choose Find Dark & Light Colors. This gives you Shadows, Midtones, and Highlights target colors. You only need Shadows and Highlights.
- Click the Shadows color to bring up the Color Picker. Click a dark color in the sky, then click OK.
- Click the Highlights color and click a light color in the sky. Skip pure white, since the sun blew it out. Pick something more yellow instead.
- If you’re not happy with a color, move it around in the Color Picker and watch how it affects the jet.
- If the shadows look too dark, click a different dark color for the Shadows.
- Click OK. When Photoshop asks whether to save the new target colors as defaults, click No.
Tip: If the Color Picker only picks white, your layer mask is selected, and the mask only contains white. Cancel out, click the Curves Adjustment Layer icon, and open Auto Options again.
Fine-Tune the Color Match in Each Curves Channel
Now refine the match one channel at a time in the Properties panel.
- Choose the Red channel and drag the curve up to add red. This sky has a lot of red, so match the jet to a cloud of about the same color.
- Choose the Blue channel and drag the curve down to add yellow. There’s no blue in this image, so you can bring it down a long way.
- Watch the bright parts of the jet as you drag. If the blue curve is too high, they look white, and in this sunset light they should look yellow. Too much yellow doesn’t look right either.
- Choose the Green channel. All the way up is too much green, and all the way down is too much magenta.
- Bring the green curve down just a little to add magenta. That makes the jet look a little more orange.
Compare the before and after. It’s night and day.
All you did was take the shadows and highlights of the sky and match them onto the jet. One Curves Adjustment Layer did it, without changing a single pixel of the original.
Optional: Add a Yellow Highlight and Lens Flare
Note: These last steps aren’t really part of color correction. They do help sell the image, though.
Paint a Yellow Highlight With Blend If
Yellow is the absence of blue. In the Color Picker, that means 255 red, 255 green, and 0 blue. The same logic gives you the other opposite colors.
| Color | Red | Green | Blue |
|---|---|---|---|
| Yellow | 255 | 255 | 0 |
| Cyan | 0 | 255 | 255 |
| Magenta | 255 | 0 | 255 |
| White | 255 | 255 | 255 |
- Add a new layer and clip it to the jet.
- Select the Brush Tool and choose a soft brush. Make it big enough to cover a large part of the jet.
- Set your foreground color to yellow. Sample a yellow from the image, or type the values from the table above.
- Paint yellow on one side of the jet.
- Double-click the layer to bring up the Blend If options. Under Underlying Layer, drag the dark triangle to the right so the yellow doesn’t affect the darks.
- Hold Alt (Windows) or Option (macOS) and drag the triangle to split it. That turns the sharp edge into a smoother transition.
- If the highlight is too strong, lower the Opacity a little.
Add a Lens Flare in Photoshop
- Add another new layer.
- Press D to get the default colors, black and white.
- Press AltBackspace (Windows) or OptionDelete (macOS) to fill the layer with the foreground color, black.
- Go to Filter > Render > Lens Flare. Choose 105mm Prime at 100% Brightness, place the flare, and click OK.
- Set the layer’s blend mode to Screen. Screen hides the black and keeps only the flare.
- Go to Image > Adjustments > Hue/Saturation. Check Colorize, make it yellow like the sun, and click OK.
Now the jet really looks like it’s flying in the sunset. The Curves adjustments stay non-destructive, so you can go back into the RGB channels and make more changes at any time.
Frequently Asked Questions
Add a Curves Adjustment Layer and open the channel with too much color, such as Red. Drag that curve down to add its opposite color and remove the cast. You can also set black, white, and gray points with the Curves Eyedroppers.
Red is opposite cyan, green is opposite magenta, and blue is opposite yellow. To remove a color cast, you add the opposite of the color you have too much of. For example, an image with too much red needs more cyan.
Go to Image > Adjustments > Threshold and drag the slider until the first black or white areas appear. Hold Shift and click those areas to place color samplers. Then click Cancel so the Threshold isn’t applied to your image.
The Midtone Eyedropper sets the grays, or midpoint, of an image. There’s no exact way to find a true gray, so click something that should be gray and judge the result. Try a few spots until the colors look right.
An adjustment layer comes with a layer mask, and that mask starts out pure white. When the mask thumbnail is selected, the Color Picker works on the mask instead of the image, so white is all you can pick. Close the Color Picker, click the Curves Adjustment Layer icon in the Layers panel, and open Auto Options again.
Clip a Curves Adjustment Layer to the subject so it doesn’t change the background. In Auto Options, choose Find Dark & Light Colors and pick the Shadows and Highlights target colors from the background. Then fine-tune the Red, Green, and Blue curves.
Yes. A Curves Adjustment Layer sits on its own layer and never changes the pixels of your photo. You can hide it, delete it, or go back into any channel and change it later.
Yes. The video used Photoshop 14.x from 2013, and nothing in the technique has changed since. Threshold, the Curves Eyedroppers, and Find Dark & Light Colors all work the same way in the current version.
Conclusion
Color correction with Curves in Photoshop comes down to one idea: to remove a color, add its opposite.
Once you know that, every curve makes sense, whether you’re fixing a cast or matching a jet to a sunset sky. Try it on one of your own photos with a color cast.
Watch the video to see each step in action, and comment on the video if you have a question.
Selections and Masking Mastery
Complete course includes 2.5 hours of step-by-step lessons, 6 structured modules, downloadable practice files, and custom Photoshop brushes. Everything you need to master selections and masks in one place.
Keep going
Next, learn the hidden algorithms for easy color correction in Photoshop.
Related Links
Final Image
Drag the slider to see before and after
Hi,
Thank you so much for your useful tutorials. Although many Dutch speak English not all of them understand English videos with technical terms. Thats the reason why I explain/translate interesting videos into Dutch. I hope you approve I did this one.
http://reinasmallenbroek.nl/photoshop.0003.html
Thanks again
Reina
No problem Reina, as long as you give credit!
Thanks!
Of course! Thanks!
Grtz Reina
Such an awesome tutorial, so simple and well explained. Thanks!
You’re welcome!
OK . BUT THE IMAGE LAYERS WERE NOT MERGED OR FLATTEN TO MAKE COMPLETE WORK OR IMAGE
Thanks! Great tutorial. Can you recommend more videos about matching colors and photo compositing?
Tom, I don’t know of any specif video, sorry.
I was curious if this was possible with Photoshop Elements. I shoot quite a bit of film and this type of correction would be useful when scanning negatives. Thanks!
jkjod,
I’m not sure. I don’t use Elements so I don’t know what it can or can’t do.
Hi Jesús. First all I’m sorry my English so I’ll try to explain me.
When you used the eyedropper tool to get samples, I think you had selected a Point sample in sample size (option bar). Is better to have selected that size to get samples or maybe the other options could help to get a better result?
Does It in relation with bit’s image (color proof?¿ profundidad de color?)? Thanks and I hope you understand me. 😉
Christian,
It all depends in the image, some of the other settings may work best in your image. Essentially what the other options do is take an are of pixels and averege it out to one color. The size of the area depends on what option you choose.
hey thanks man, now i totally understand the rgb and color correction.thanks
You’re welcome!
Can i get the ps action file of this effects
There is no action for this tutorial, I’m not sure what you’re referring to.
I am not able to download the files for this tutorial, not sure why. Any help would be greatly appreciated. Really enjoy your tutorials.
.
Wayne, if you are still having issues downloading the files please email me through the contact page. Thanks!
Excllent! Great for revising stuff I had forgotton. Just enough infomation, not over explained. Perfect.
Thank you!
You made colour correction very simple to help me understand the complexity behind.
Thanks
You’re welcome!
Is it only possible to see this tutorial once because we would like to see it again and it won’t work.
You can see it as many times as you like.
It’s a regular YouTube video! 🙂
Your tutorials are helping me to understand certain things easily, things and concepts I had been looking for to understand for a long period . Thank you for your time and effort. Sorry for potential grammar mistakes, english is not my first language.
You’re welcome! And no worries, English is not my first language either!
Great tutorial (plus other ones that you made thought me a lot) and with manny, manny thanks for these learning opportunities.
Thank you!
Wonderful tutorial. Regarding the exercise files: I don’t see a download link.
Hello,
I have a question concerning the CMYK blending with C + M + Y + K colors in Multiply mode.
Do you work in the CMYK mode or in RGB mode?
For me in CMYK mode it does not work (PS do not “accept” certain RGB colors which are C M Y ). And when I do it in RVB mode the result is a bit different. The colors are too much saturated. I cannot find where is the error.
marvelous work you doing sir, you inspire me to to be better at what i love doing and your teaching technique is so wonderful, thank you for sharing your knowledge and findings to the world……
Hi, thank you so much for this beautiful tutorial!
Unfortunately, I can’t find the practice images for this tutorial.
Where can I find the ‘zip file’ you mentioned. Thanks again even though
they are not available now. Anyway, I’m a beginner who is getting so obssessed with
photoshop at this age of 65.
I can’t find the download for the tutorial. Would you please post the link.
Gret tutorial but I can’t find the exercise files. Would you please post the link.