Introduction to Curves

The Curves tool is a powerful way to affect the contrast and tonal response of a photo. Although it may look intimidating at first, it’s actually quite simple. To add a point, just tap or drag anywhere along the curve. To remove a point, just drag it left or right past its neighbor.

Shadows, Midtones, Highlights

Looking at the Curves interface, the left half controls shadows, the middle controls midtones, and the right half controls highlights. To brighten or darken any of those zones, just touch and drag it up (to brighten) or down (to darken).

The ‘S’ Curve

One common way to increase contrast in an image is known as the ‘S’ Curve. To create an S Curve, just lower the shadows while raising the highlights. It looks like this:


You can create an S Curve with only two taps using Mattebox. Just tap once above the line in the highlights, and below the line in the shadows. Instant contrast!

That ‘Faded’ look

Everyone loves that film-like ‘faded’ look, and it’s extremely easy with Curves. Just drag the point in the lower left corner straight up:


If you lose too much contrast, it’s easy to restore: just combine the Faded curve with an S curve:


Color Correction

It’s easier to perform color correction using the Color Balance tool, but you can also affect the color balance of the photo with Curves. For example, if you need to add green, you can select the Green curve and drag the midpoint up slightly.



If you pull the curve so that it dips down, you’ll create an effect known as solarization. When the shadows are solarized, they actually get brighter instead of darker. Especially in black & white images, this can be an interesting technique. Give it a try!



By playing around with the RGB curves, you can achieve a huge range of effects, from subtle to extreme.


Import and Export

If you have Adobe Photoshop ACV curve presets, you can import and edit them in Mattebox. To export, tap the “•••” button in the Filter panel, or press and hold the Save button in the Editor. You can then email or message the ACV to yourself or a friend.


Find out how to make adjustments with absolutely no interface, in Multitouch Gestures.