Photoshop Color Correction: Deep Dive into Curves for Precision Editing

Let's talk more about color correction. While the color balance was a nice way to get started because it helped you to see the color wheel without having to remember it, something that is gonna offer you more control and more options is curves. When you first look at it, curves will not be an intuitive thing, but once you understand how it works, it gives you a lot of control and very targeted specific control over how you want to change your image and is, in my opinion, the best way to do the color correction compared to something like color balance, which is much more basic.

So when you look at this image, hopefully you can see that even though there's a lot of blues, look at the whites and hopefully you can see that there's some warmth, some yellowness to these that needs to be corrected. These whites should be a neutral, clean white. This image overall is too yellow.

So just as a reminder here, let me open up my color wheel here. Remember that yellow and blue are opposites. So if something is too yellow, we need to go more blue.

So we need to make this image cooler, right? Green and magenta are opposites. Cyan and red are opposites. So the cool colors that we wanna go more towards, we'd wanna go more towards the cyan.

We don't wanna go more towards the blue. So less yellow, more blue. Less red, more towards the cyan, okay? So that's how we're gonna compensate for this.

And we're gonna do so using curves. We're gonna do this as an adjustment layer so it's non-destructive and we're gonna do curves. Just remember, if you do image adjustments, those are destructive.

Layer adjustments are non-destructive. So this is a way to do your layer adjustments, which is the same thing as going into layers and adding adjustment layer for curves. And I'm gonna close this color panel by double clicking on it to close it up so we have more space dedicated for this.

And I'm gonna make this area bigger so we can see this better. So I want you to see this curve nicely. Okay, so when you first look at this, you're like, oh, this is so intuitive.

I know exactly what to do. No, I'm just kidding. The first time you look at this, you're like, I don't even know what to do.

Where do I even start with? So what am I looking at here? There is a composite, red, green, and blue, where we're working with all colors simultaneously. Then there are the red, green, and blue channels. Now, let's start with the RGB, the composite.

What you're looking at here, there are peaks. And this thing right here, this is called a histogram. The histogram is showing you how many pixels you have in a certain part of your tonal range.

So when we talk about tones, mid-tones, highlights, shadows, we talk about lights versus darks. So in this image, notice there's a lot of light areas, and there are only a couple dark areas. Mostly this is middle tones and light tones with very few darks.

So look over here. Black is on the left, middle gray is in the middle, and then white is on the right. The higher the peak, the more pixels we have in that part of the tonal range.

Look at how there's only a tiny little peak down here in the darks. That is the dark pixels. We do not have many of those, so it's a very small peak.

Then we get a bigger peak here as we're getting brighter, but this is still not bright. Bright is all the way over here. This is white.

Notice we have lots of peaks over here, and we get fewer and fewer as we get darker. We don't have any things that are pretty dark. We just have a few that are really dark.

And then this, which is getting into these darker things like her shirt, that's not a big portion of the image here. So while it does peak up higher, it's not as high as some of these other areas, which are these kind of white walls, which aren't quite pure white because they have some shading to them. They are a little bit darker than the brightest white because they're not solid, blown-out white like this would be over here.

So that just kind of gives us an idea of where color is in our image, where brightness is in the image. So when we're looking at the red, green, and blue composite, this is about brightness. No color individually.

We're not changing the balance of colors. We're just changing brightness. Now, if I go into the red, I can see the distribution of where red is in the image, where green is, and where blue is.

Okay. Now, when we look at something, what is problematic is flat-lined areas where there are no pixels at all. Most images, typically speaking, will be a range of some blue, green, or red somewhere in the image, all the way from shadows to highlights, all the way from black to white.

These are black and white points. When we see a flat line like this, where there's no peaks at all, that means there's no pixels in that part of the tonal range, which in a way means we're kind of wasting the potential. There are no really bright blues.

There are no really bright greens. There are no really bright reds. Now, red is not as bad here, but it does kind of flat-line there a little bit.

The shadows are fine. Notice how there is some stuff down here, and there's no flat-line area there in the red, the green, even though there's not much, there's still a little bit there, and the blue, but it's the highlight area. So what I'm gonna do is I'm gonna not do them all at the same time, the RGB composite.

That means changing red, green, and blue simultaneously, all at the same time. I'm gonna go to red, and I'm gonna say, let me pull this potentially brightest red, and let me pull it over to where I actually have some pixels, where the peaks, where there's a little bit of something starting. I'm gonna do the same thing with the green.

Basically, I'm just trimming off the dead area where there's no pixels. And so I'm gonna pull this one over here. And so all I did was kind of trim off that.

Now, I only had to do it in the white areas on the highlights, but if you also needed to do it in the shadow areas, we might also do it there. Now, look at the image. I was not even looking at the image as I made this change.

Look at how much better that image looks. Wow, so much better. I didn't even look at the image.

All I did was kind of cut off the dead spots. So let's just do this again, just so you can see. Okay, this is how bad it was before.

All I did was I went to curves, I went through each color individually, and I trimmed off the dead areas, whether that be on the black point or the white point. And I just brought that over until I kind of hit some pixels, until the peak started going up there. You do it on either side, although this particular image only needs it on the white side, on the highlight side.

And you pull that over, and then you look, and look at that. In many instances, I can't say for every single image, but in many instances, this will color correct your image. And it looks amazing.

It's wonderful. Now, effectively what I did was I adjusted the white point. So I balanced, some of those came in more than others.

So if I switch back to my composite, here I can see I have a good distribution of some darks, some mid-tones, some lights over the whole area without really having any dead flat areas. Now I do see the different colors, right? The things that I went individually here, the red, greens, and blues. Notice how I changed blue more than I did green, which I did more than red.

Now remember, I did say that this was mainly yellow, right? It was the opposite of blue, right? So blue and yellow are opposites. So if it was mostly yellow, and I made the biggest change to blue, that would make sense, right? Now I don't have to see all the individual colors here. Sometimes that gets a little overwhelming to me to see all of that stuff.

I actually like to go into the menu up here for the properties panel. And I like to go into my curve display options. And I like to turn off those channel overlays because I think that's just a little too much.

Because what you wanna do here on the composite is you want to adjust your contrast and brightness. The idea is that color channels affect the balance of colors. And the RGB composite is how bright the overall image is.

So for example, if I bring in this white even more, my brights get even brighter. And if I bring in this black point more, the blacks get even darker, which I don't wanna do because I've already got a good white and a good black. But I might wanna change the middle tones.

So here, if I go to the middle tones, notice here on the bottom, these are the tones that I'm working with. This little gradient shows you from black to middle to white. Those are the tones you're working with.

Now over here, notice that the side gradient is going from black to white. That means if you raise those tones up, they will get brighter. And if you lower those tones, they will get darker.

So as I put a point here in the middle tones, so I'm working with those mid tones, then when I drag down, it'll make those darker. So I can make those mid tones darker and look what happens with the brightness of my image. Or if I drag them up, I'm making those middle tones brighter.

But what's nice about curves, which you lack in things like the brightness and contrast, which is very heavy handed, it's just one slider. Here, you can put a point for your mid tones, you can put a point for your highlights and look at how I can change the highlights and the highlights and the shadows differently. Now the shadows are, there's not a lot of shadows, but notice down here with the shoes, notice how the shoes are changing there.

And there are some shadows here on her as well. So the idea is that you can put these points and if you're working with the darks, which is not black, it's darker shadows, you can raise them up to make them lighter or make them darker by dragging down. So which way are you dragging? And if you want them to remain the same, you can just put those points and keep them the same, but then you can drag up to make the highlights lighter or darker.

So if I wanna pull those highlights down a little bit to bring a little more detail back, I can do that. So this gives you more targeted control over where your brightness and contrast is being added. Now, if you think about what I did with the color, I pulled those points in individually.

I was doing what's called setting the white point. Now, let's say I just wanna get rid of all this work that I've done here. There's a reset button here.

So if I just hit reset, this just goes back to the default. I got rid of all the work that I did. I'm back to my horrible, ugly color that I started with.

There are tools in here which you can use that the idea is if you know something in your image should be white and you can see it. And you're like, if I could just click on that and tell it to make that white, it could do that for me. That's what the set white point tool does.

So setting the white point, when I click on it, I then choose something in my image. And when I click on that, it makes that pure white, not a yellowish white, not a reddish white or whatever it is, it makes it pure white. That's like going in and setting those white points.

The only problem is that it makes it pure, absolute white with no detail. And they're probably, that wasn't quite white. It was probably like a gray that, yes, it was color neutral, but it wasn't pure, blown out, no detail white.

So that's the thing you have to be careful about when using this tool is that will make that white with no detail. So it can pull this point over too far. Remember when I was showing you this, I only wanted to come over to right around here because the more you come over, anything to the right of that is pure white.

So things that had tonality, that had some detail, they no longer have detail. So that's called clipping. You wanna be careful about clipping your highlights or your shadows.

You only want this to come over and just touch there. You don't wanna go too much farther than that or you'll clip and lose detail. So this tool is a little heavy handed to begin with, but we can customize it.

So I'm gonna hit the reset button to just get rid of all that. And I'm gonna double click on this tool. Now, sometimes when you try to double click on this tool, it doesn't come up with the options.

So I have to click on the icon down here and then I can double click on the tool and it will work. So if it doesn't work and you're like double clicking away and it doesn't work, just come down here. Instead of being on the mask, click on your layer here and then you should be able to double click on the tool to customize what that tool does.

And so the idea is it's setting it to a pure white. Hue, nothing. Hue is the color, there's no color.

The saturation, the intensity of the color, there is no saturation. Brightness, 100% brightness, pure blown out white, no detail. I probably don't want this tool to set the thing that I click on to 100% brightness.

The chance that I'm clicking on something that is absolute pure blown out white, most things have some detail to them. So you probably wanna bring this down four, five or 6% down. So maybe like a 96, a 94, a 95%, somewhere around there.

So let's say I go down 5%, I go down to like 95%. So it's not quite white, it's more like a gray, but neutral. No hue, no saturation, I just toned it down so it's not blowing out all my detail.

When I click okay, I'm changing the definition of what this tool does. And it says, hey, do you want that to be the default from now on? Yes, that's a better default. Yes, that's the default.

Now when I click, it sets that to be the 95% brightness. So it doesn't pull things in quite as much. That's a better amount.

That's a better amount. That's a much better amount. So it didn't pull them over as much as 100% brightness did.

Now you can also, if you need to change the black point, you could also do it with the black point tool. But in this image, the black points are perfect. I really just needed to change the white points.

So I'm only changing it for the white point tool. Great. Now, I still had to click on something that I thought should be pure white, and then Photoshop made it pure white by just kind of pulling in those things.

And by the way, if it didn't quite get it perfect, you can always adjust these things. Keeping in mind that when you go to blue, as you go one way, you're gonna get more blue, and as the other way, you're gonna get more yellow. Because blue and yellow are opposites.

But instead of you having to click on something, could maybe Photoshop detect the point to click on for you automatically? Let's try that. So I'm gonna hit the reset button here to just get rid of all the work I've done. And this is where we can say auto.

If I click auto, it automatically tries to figure it out. Now the default auto, it's not so great. It often messes it up.

It doesn't quite get it right. There are a couple different ways for it to guess, different computer algorithms. And you can see those additional things if you option click the auto button.

In fact, when I hover over, it says use option for options, meaning option click on the Mac or alt click on Windows. So if I option click or alt click on Windows, I bring up different ways for it to guess. And you can go through each one of these and see what in fact you think works best.

This one, not so good in this case. Now, maybe on some images that would work great, but not on this particular image. So this one, this one, this one.

So that one's not good. That one's not good. Maybe one of the two middle ones.

I think they're very similar. I kind of like the darker one. So I'm gonna go with that one, but either one, they're very similar.

I could also try snapping neutral mid-tones. Sometimes if you have a color cast in the middle areas, then that can help to remove that color cast in those middle mid-tones. In this case, it doesn't really make any difference.

So it doesn't matter whether I have that on or not. And I'll click okay. That essentially did that clipping for me.

So it went in and it pulled those in so that I didn't even have to click on something. So as far as trying it out, what I would say is you could just start with an image, go into curves, option or alt click on auto, and just try each one of these things out and see if it can guess. I'm not saying it'll work all the time, but it does work a lot of times.

It can do an amazing job. I think in this case, I kind of like this one. And then even if it's not quite perfect and you want to customize it, you can still go in and you see what it's done, which is what I started with.

If you want to go a little further and pull that in, you can. So you can do things manually or you can do things automatically. So let's see this again on a different image.

So here I've got this image and I've also got this image here. So let's see the same thing on these two. Let's do it on this one first.

Now this one, not a horrible color cast. In fact, it kind of has a certain vibe, kind of like a low contrast, kind of, well, let me ask you, what color balance or color imbalance do you see? Maybe you don't see one, maybe you need to try, maybe we need to experiment. So we're gonna try this with a curves adjustment.

Now look at each color channel. Look at how big of a dead spot there is, not on the shadow side, but the highlight side. And think about, do I have any really good, pure, bright whites? No.

I do have some blacks, but I don't have a, I have light things, but they're not pure white. So all of these, I kind of need to bring this over, which I could manually do by pulling each one of these over. I could manually do this and I could see what it does.

So notice now I have something that's a little bit more contrast and has taken off some of that extra warmth that was there. Now, again, we're trying to color correct. Now you might like the vibe, you might like that certain color, that warmth, but if you're trying to talk about color correction and being color neutral, this is more neutral than the original was, even though you might like that feeling, that vibe that it has.

You can always go with that if you want. So I can manually do this. I could also, if I get rid of those settings by hitting the reset button there, I could option click or alt click on Windows on the auto button, and I could try each one of these and see which one I like.

In this one, let's see here. This one's more neutral. This one's way too pinkish, I think, in my opinion, but I could try neutralizing the midtones.

Ooh, that definitely helps that one out a lot. This one's a little bit brighter though, but this one's a little bit more kind of warm pinkish. Depends on which way you wanna go.

I think this is more neutral in this case, so I would probably go with this. You can see the before and after here. I didn't even have to click on anything, but it went in and essentially pulled that over, just like we saw before, but it did also make points on the midpoints as well.

So the idea of the midpoints is after you've got a good black and white point, you've set the highlights and the shadows. The middle tones might have a color cast as well that you wanna more compensate with. So for example, I can go to blue, and remember, blue and yellow are opposites.

So if I drag up, notice how it makes it more blue because I'm brightening it. I'm adding more blue light. If I drag down, I'm removing blue light, which means I'm going more yellow.

So dragging up is more blue. Dragging down is more yellow. And so you can play with that, and you can make it the way you like the feel.

It doesn't have to be correct. If you don't want it to be, you can go with whatever feel you want. Now, green and magenta are opposites.

So if I add more green light by brightening it up and adding more green light, it's gonna get brighter and more green. If I drag it down, it's gonna remove the green light, which means go more magenta, more pinkish, right? And you might like that, right? And then you can go to red, where if you push up, you're adding more red light, or if you pull down, you're going away from the red and you're going more towards the cyan, right? So you can always do things manually. Now, I'm gonna reset this one more time.

I'm just gonna hit the reset. If you wanna click on things, I already set my white point eyedropper. So this white point one here, if I click on something that I think should be white, even though I put it down to 95, it's not blown out white, that makes that a neutral white.

But I might also need to do the same thing for let's say shadows or the mid-tones. So with the shadow one, that normally set to pure black, that when I click on something, it set that to 100% pure black, which might clip off too much shadow detail, just like we saw in the highlights. So if I were to double click on the black point, no color, no saturation, no brightness, but that means it's completely black with no detail whatsoever.

Just like I pulled down the highlights so that I kept some detail in the highlights, I probably wanna push up. If I came down 5%, I probably wanna go up 5%, four, five, 6%, somewhere around there. So now it's gonna be a very, very dark gray, but not quite full on black.

So I'll keep a little bit of detail. So I do want that to be a default target from now on because I don't wanna blow out my shadows. And now when I use this tool from now on, when I click on something, it doesn't quite go as dark black, losing all the detail in that.

So the whole idea of these tools is that you click on something that should be color neutral black, or you click on something that should be color neutral white. And if you have something that should be a color neutral gray, this middle one here is the gray. Now, not all images have a neutral gray.

I don't have to customize that because it should be a middle tone gray. The idea is when you click on something that should be gray, it'll make that gray. Now, the thing is, should that be gray or should that really be a warmish kind of wood? Maybe the plate shadows are actually the thing that should be gray, leaving the wood to be kind of warm because it is wood.

It probably is not a complete gray with no color. So you do have to look at your image and say, this is what I think this should be in the image, knowing something about that image. And when you set that gray point, it's going in to each of those curves and setting a point and pulling up or down to neutralize that, to make it a neutral gray.

So let's do this one more time. If I go into Curves, in this case, let's take a look at color by color. The highlight is okay, but the shadow needs adjusting.

The shadow needs adjusting. You're pulling off those dead areas. Here also, the highlights need adjusting.

So I pull that in, just come until you hit something, cutting off those dead areas that you don't want. And look at the color adjustment that I've done. Now, the original image had a certain vibe, a low contrast kind of cool vibe.

You might like that vibe. But as far as color neutral, color correction, this is a more corrected color, a more correct color than what I started with. Could I try doing the auto settings instead? Oh, let's try it.

Let's hit the reset option or alt click the auto button and just see which one do I like. That one I like the color of. Let me snap neutral mid tones here.

I think I like the color of that. I kind of like the contrast of this, but the color of this. So I'm gonna go with the color of this because I can always add contrast, right? I can always pull this over.

See, there's a little flat line here. So if I pull this over, that will increase the contrast because I was wasting the darkest dark on pixels that didn't exist. There was no peaks here.

No pixels are using that black. So if I pull this over to pixels that I have, now I've reassigned black to pixels that I have and that increases the contrast. Nice.

Or if I hit reset, I could also use my white point dropper to click on something I think should be white. Use my black point to click on something that I think should be black. And if there was a neutral gray, I could use my gray dropper.

Don't force that though because not all images have something gray. I don't think this plate is exactly pure gray. And if I click on it and it makes it pure gray and I think it was supposed to be warm, it throws the color balance off because I don't think that was supposed to be an actual, like totally neutral gray.

So I'm gonna undo that. And yeah. So just keep that in mind that there are different ways you can approach this.

But all of these, whether you're doing the auto, whether you're clicking on these different parts to try to get it to do this for you, in the end, they are going and adjusting each individual color channel for you. You can always go and do them yourselves. And then you can adjust the balance yourself as well.

So with the blue, I can make it more cool or more warm, depending on which way I drag. And if you wanna make something more warm, you probably want it to be more yellow, but also not yellowy, like yellowed. It doesn't look very good.

Red and yellow make orange. So a lot of times you wanna add some yellow and then go to red and add a little bit of red. And that adds a really nice glow, a nice warmth.

And I think you can really see that if I went back to here, if I wanted to make this a bit more warm, I wouldn't just go to blue and make that a little bit more warm with the yellow because it looked yellowed. I would go to the red and I would add a little bit of red as well. And the red and the yellow together make a nice orange and makes some nice warmth to that.

So hopefully you can see now with these curves that while the interface is more confusing initially, hopefully now you've seen how this works and how you can control it. And there's a lot of power to do exactly what you want using curves. Curves can be great for color correction.

It can also be great for just contrast adjustments too. Say I throw that in the trash there. If all I want to do is change the contrast, I could just do a curves adjustment and say, let's say darken the darks, brighten the brights.

And I just played with the contrast. But again, you can do say, oh, I only want to brighten the brights or I only want to darken the brights. You can individually control exactly the contrast and the color that you want.

So you get the most control out of curves. It's just not the most intuitive, which is why I didn't want to start with that. But this is how I normally do my color correction is using curves because you get the most power, the most control out of it.

And so I hope this has been worth going through and learning this. Try this out yourself in Exercise 2D.