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Remember when I talked about Levels? and how you can use it to increase the contrast in your photos?

Well. Get ready to do even more. With Curves!

Remember with Levels, we could adjust the black point, white point and mid-point? With Curves we have the ability to adjust up to 15 points, and because we’re moving these points in a 2-dimensional way instead a 1-dimensional way, we have more control over how we can adjust the photo, too.

First, let’s open up the Curves dialog by going to Colors –> Curves:

You can see the same histogram that you did in the Levels dialog, but now we have a diagonal line we can move instead of just three points to move side-to-side. The idea is still the same though – dark tones on the left and white tones on the right. In short – moving anything above the line makes it lighter and moving anything below the line makes it darker. For instance, if we were to take the left-most point and move it all the way up to the upper left hand corner like this…

…we get an image that’s completely white.

So how would we really use this Curves thing? Let’s take a look at this photo:

Let’s adjust the contrast using Curves. First we’ll move the left-most dot to the right – in the exact same manor that we would have moved it in Levels – until we get to the point in the Histogram that it starts to rise up:

Here’s what the image looks like now (original image on the left, new image on the right – it’s a very subtle difference):

At this point, if were still using Levels our next option would be to move the white slider to the left, the equivalent in Curves is to move the top point to the left (along the top of the histogram):

… which we can do, but since there’s already some blown highlights in this photo, that would blow them out even more (once again, original on the left, edited on the right):

By the way, notice how my line is steeper now in the Curves dialog – the steeper the line, the higher contrast there is in the photo. As an aside, if you made the line less steep, like so…

…the photo would actually lose contrast:

…which I don’t like, so let’s go back to our image. I didn’t like moving my white point, so let’s look at the real power behind Curves over the Levels dialog. In Levels, I could move the midpoint, but there was only ONE midpoint. In Curves, we can create points anywhere on the line to move around, so let’s make an S-shaped curve instead:

Check out the difference it makes:

I like this, and so I’ll save this as my final image:

There’s a lot more to Curves than just this, but I’ll leave you with that much for now, hopefully it’ll make a difference on some of your photos!

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