Join Tim Grey for an in-depth discussion in this video The curves adjustment, part of Targeted Adjustments in Photoshop CC.
- One of the more sophisticated adjustments in Photoshop is the Curves Adjustment, and in fact with Curves, you can apply something of a targeted adjustment without the need to use a layer mask. Now that's not to say that you would never use a layer mask in conjunction with a Curves Adjustment Layer, but then in some cases, you may be able to apply the targeted adjustment you're looking for using Curves without the need to add a layer mask, and that can include both tonal adjustments and color adjustments. Let's take a look at the concept here.
I'll start off by adding a Curves Adjustment Layer, so at the bottom of the layers panel, I will click on the Add Adjustment Layer button, and then I will choose Curves from the pop-up menu, and I will add a Curves Adjustment Layer on the Layers panel, and you can see I have the controls for the Curves Adjustment on the Properties panel. And the basic idea here is that we can adjust the shape of the curve to adjust the overall appearance of the photo. So I can drag the curve upward, literally just click on the curve and drag upward in order to brighten the image, and I can drag downward to darken the image.
When I click on a new point on the curve, I'm actually creating an anchor point. So if I release the mouse here, you can still see that I have an anchor point, a handle essentially, for that curve, and I can add multiple anchor points, multiple handles to adjust the shape of the curve. And so, for example, I can move that anchor point down over toward the shadow end of the range. You'll see my gradient down at the bottom, dark on the left, bright on the right, and so if I put an anchor point over toward the left end of my curve, into the dark shadow areas, then I can emphasize a brightening adjustment on the shadow areas.
Of course, at the moment, I'm adjusting the entire curve. I'm brightening the entire image, but I can use additional anchor points to normalize that curve in certain areas or maybe even darken the highlights while I'm brightening the shadows, obviously in this case, an extreme exaggerated version of that type of adjustment, but the point is that I can apply some adjustments that affect specific areas based on their tonality, so maybe tone down the highlights just a little bit, and open up some shadow detail, or the opposite, very common as well, to darken down the shadows and brighten up the highlights to enhance contrast within the image.
So I'll moderate that adjustment just a little bit, maybe a little bit of an additional contrast in this case, but again, the point being is that I'm applying a different adjustment in the shadow areas versus the highlight areas, in other words, a targeted adjustment based on brightness values, and I can perform a similar adjustment as it relates to color balance. Normally in Curves, we're working in the RGB channel, the composite channel, so that we're affecting overall tonality, but I can choose the red channel to shift the balance between red and cyan, the green channel to shift the balance between green and magenta, or the blue channel to shift the balance between yellow and blue.
And in this image actually, as it turns out, if I choose the blue channel, I can adjust the overall balance, but notice that the bright areas are a little bit more yellow, and the dark areas are a little bit more blue, and I might want to compensate for that. So in the context of an individual color channel, dragging upward will brighten that channel, which adds the color that the channel represents. So here I'm increasing the value for blue, and so the image is shifted toward a more blue appearance, and if I drag downward, then I'm shifting toward a more yellow appearance.
And so in this case, I actually might want to focus that color balance adjustment differently in the shadows versus the highlight. So if I were shifting toward yellow away from blue, I might want to focus that adjustment on just those shadow areas, and again because I'm only using a single anchor point at the moment, that adjustment is actually affecting the entire image, but I can add an additional anchor point, maybe even more than one additional anchor point, in order to refine the shape of that curve, so if I'm dragging the curve upward, in the highlights range, then that is shifting the color balance for the color highlights toward a more blue value, and I've dragged downward, down in the shadows range for my curve, again, on the blue channel, and so that is adding a little bit more yellow, the opposite of blue in those shadow areas, so kind of mitigating what seemed to be a little bit too much blue in the shadows, and then taking away some of that yellowish appearance in the highlights targeted adjustments, in that case, a color balance adjustment essentially with different results in the shadows versus the highlights, so targeting again based on brightness values or luminance values in the image.
So the Curves Adjustment enables you to apply tonal adjustments, lightening, and darkening, and fine tuning contrasts for the overall image in specific areas, so focusing on just the highlights, or just the shadows, or a combination of both, and then targeting a color adjustment similarly based on tonality, so a targeted adjustment for tone and possibly color without even needing to use a layer mask.
- Balancing subtlety and accuracy
- Working with black, white, and grey on a mask
- Targeting without a mask
- Painting a targeted adjustment
- Making a selection-based adjustment
- Editing or duplicating a mask
- Working with multiple adjustment masks
- Fine-tuning a mask