Besides using Curves for color correction, this is my main tool for creating contrast, because it gives you a range of control you really can’t get any other way. Of course, in the past, you really had to know Curves inside and out to tweak individual areas of your image, but in Photoshop CS4, Adobe introduced the Targeted Adjustment Tool (or TAT for short), which lets you click-and-drag right on the image, and the tool will tweak the right part of the curve for you automatically. It’s way cooler than it sounds.
Here’s a pretty flat-looking photo that could use a Curves adjustment to bring more contrast to the photo and, as I mentioned above, we’re going to use the TAT (shown circled in red here), so we really don’t have to mess with the curve at all, we just have to tell Photoshop two simple things: (1) which area of the photo we want to adjust, and (2) if we want that area to be darker or brighter. That’s it—and we do the whole thing using just our mouse. So, start by pressing Command-M (PC: Ctrl-M) to open the Curves dialog and clicking on the TAT.
Now, move your cursor outside the Curves dialog, and out over the part of your image you want to adjust. In our case, we want to make the neck of our blue heron darker. Start by clicking-and-holding on the blue part of the neck, and you’ll notice that your cursor turns into a hand with a two-headed arrow, pointing up/down. That tells you that dragging up/down will make the adjustment. In our case, we want this blue area darker, so drag downward. As you do, it knows exactly which part of the curve to adjust to darken that area. Now move just to the left, to the purple feathers (the tool’s shown circled here), then click-and-drag downward again to darken that area.
So, now that we’ve darkened the blue and purple feathers, let’s go make the white feathers on his chest brighter. Move your cursor over these feathers, but this time you’re increasing the brightness, so you’d click-and-drag upward (rather than downward). As you do this, it knows exactly which part of the curve to adjust to affect that area (if you look at the curve, you can see a new point has been added on the top right of the curve—that was added when you clicked-and-dragged on the white feathers).
Lastly, now that we’ve darkened the bird, let’s brighten the water behind him by moving our cursor over to the lighter area up in the top-left corner, and clicking-and-dragging upward to brighten that area (also note where it added a new curve point, and how it adjusted that new point upward). This is so darn easy to do, but as you can see, it’s also pretty darn powerful.