Monday, May 31, 2021

How to Use Curves to Change Contrast and Tone in Photos With Lightroom Classic

How to Use Curves to Change Contrast and Tone in Photos With Lightroom Classic

As photographers, we're visual by nature. From making an exposure to printing, we want to share the way we saw the world and express how it felt. It's a major bonus if the tools we use are built with this process in-mind.

In Adobe Lightroom, the tone curve is so much more than a technical read-out: it's a powerful tool that gives you all the visual indicators you need to correct an image accurately and make intuitive creative adjustments.

Tone curve for adjustmentsTone curve for adjustmentsTone curve for adjustments
Lightroom's tone curve is more than an indicator—it's actually a tool you can click and drag to correct tone and contrast.

In this tutorial, you'll learn a fast and powerful way to make tone and contrast changes. We'll leverage the tone curve to make those adjustments, following the shape of the histogram for correction.

1. Definition: Tone and Contrast

Let's start off by defining our two key terms, tone and contrast.

Every image has what's known as a dynamic range. All the pixels in the image all fall into discrete tones within this range, and we can measure the dynamic range by finding the difference between how white the brightest point is and how black the darkest point is. Tone doesn't describe the content in an image, but understanding and discerning tonality in images is still very helpful in photography. A related term, contrast, describes the distribution of those tones in the image and how they relate to each other and the content.

For example, a high-contrast image has pixels on or near the full spectrum of the dynamic range, with a distribution of highlights and shadows throughout the image. You might hear an image referred to as "high contrast" when there's a wide range of of highlights to shadows. A low-contrast image contains less difference between bright and dark. It might have it's pixels high or low on the range, but all in a smaller tonal range.

High contrast low contrast LRHigh contrast low contrast LRHigh contrast low contrast LR
The left panel shows a high contrast edit, while the version on the right is a compressed tonal range, low contrast edit.

If you want to learn more about tone and contrast, check out the alternative contrast-control method described in our other tutorial. It includes more examples of tone and contrast ranges.

The Art of Image Correction

Before we learn how to use curves for tone and contrast corrections, it's important to mention about the idea of image correction. When you jump into an app like Lightroom, there's a temptation to start pulling every slider in the Develop module. While it's fun to experiment with these tools, it's best to approach the app with a "process" mindset, adjusting an image step-by-step.

When you begin to work with the settings that impact the look of an image, start by correcting the image, applying a limited set of adjustments that bring the image to a neutral state. With these changes, your image might actually appear slightly less true-to-life and over-exposed. That's OK, tthe idea is to bring the picture to as clear and readable as you can, balancing exposure, white balance, saturation, and contrast. Doing these steps first makes it much easier to apply creative adjustments later.

If you want to learn how to correct your images, we have a complete set of tutorials to help. Jump to any and all of these links to learn about the correction process; each of these techniques work on different visual elements.

2. How to Use Curves to Correct Tone and Contrast

When you shoot images in RAW format, they'll invariably need post-processing to come alive. One technique for tone and contrast correction is to use combinations of the exposure, contrast, and highlights and shadows sliders. We'll make the same adjustments by reading the histogram and adjusting the tone curve. You can also use curves in conjunction with other tools.

Let's look at a sample image below, which is a bit flat and lacks contrast—typical for a raw photo. I've already applied my basic corrections to white balance and exposure.

The adjustments take place in the Develop module. Find the Tone Curve section, and notice the graph that shows a histogram representing an image along with a white line. The white line is the curve we can control to adjust the tone curve.

Sample image Lightroom tone curveSample image Lightroom tone curveSample image Lightroom tone curve
The white line overlaid on the histogram is the tone curve, an adjustable click-and-drag tool.

Make sure that you've selected the white circle, second icon from the left (next to the red circle) just above the tone curve. This will put us in Point Curve mode, which transforms the curve into a usable point-and-click tool.

Now, let me make a recommendation: let's start with a tone curve preset. If you're working with an image that isn't fully corrected, this is the best approach. Click on the dropdown next to Point Curve, and let's start with the Medium Contrast option.

To get a feel for what this tool does, it helps to compare the medium preset to the strong preset. Check out the comparison in the screenshot below.

side by side tone curvesside by side tone curvesside by side tone curves
The curvier the tone curve, the more contrast and tonal range you'll add to your image.

Using this tool is fairly intuitive. A flat tone curve means your image will be more flat in its contrast and tonal range. With more shape to the tone curve, your image will take on more tonal range and contrast. Moving the curve towards one corner or the other introduces contrast and tonal changes in different parts of the image.

Side by side curves appliedSide by side curves appliedSide by side curves applied
These are the resulting images from the two tone curve presets shown above.

The best way to learn this tool is to try it. After you a pick a preset, you'll notice new circles added to the tone curve. These are the control points you can you use to click-and-drag to adjust the shape of the curve. Remember, Lightroom also lets you undo changes (make sure to use the History panel on the left side to walk back adjustments) without loss of quality, so experiment with the tool before we go any further.

Reading The Histogram

The left side of the tone curve controls the contrast in the shadow regions of the image, while the right side of the curve controls contrast to the highlight image areas. Midtones are in the middle, black and white points sit on either side.

Check out the example below, then compare the shape of the tone curve to the previous example. To illustrate adding high contrast to the shadows, I pulled the control points near the left side down and to the right.

More contrast tone curveMore contrast tone curveMore contrast tone curve
Pulling down the control points on the left side of the curve adds more contrast to an image.

Now, let's explore creative adjustments to the highlights in our image. For this example, let's say that we actually want less contrast in the highlights, to give this picture a more film-like tonal range and appearance.

I've taken the rightmost point on the tone curve, white, and pulled it down, flattening out the tone curve in the highlights. In doing this, you'll notice the image loses contrast in the mountain areas. In reducing the "curve" to flatness, the highlight contrast is reduced. This change makes it feel like the mountains are far away in the distance, occluded by atmosphere.

Low contrast highlights LightroomLow contrast highlights LightroomLow contrast highlights Lightroom
Flattening the tone curve on the right side will "crush" the highlights, reducing the contrast.

As another alternate example, let's return the white point and bring back more highlight contrast. Below, I've dragged the curves on the right side upward. The result is much more contrast between the sky and mountains in the background: this makes them feel like they have much more dimension, rising above the foreground.

Alternate example highlights LRAlternate example highlights LRAlternate example highlights LR
With more shape to the right side of the tone curve, you'll see more contrast in the highlights.

The tone curve isn't just a chart. In Adobe Lightroom, it's actually a click-and-shift tool that you can use for adjustments. For visual artists, it's sometime much easier and more intuitive  to explore the relationship between the tone curve and the image's appearance.

3. Next Steps for Your Photo

Ready to keep going with your photo in Lightroom? Here are more free tutorials to take you there, including how to use your new skill with curves to make creative colour adjustments in Lightroom Classic.

The Best Source For Creative Adjustments For Adobe Lightroom

We've been using tones and curves to apply corrections to an image. That means that we used Lightroom's tools to bring the image back to a neutral state, not unlike how it appeared in real life.

While you were working with these tools, you might have started to daydream about creative adjustments. These changes take your image from corrected to fulfilling your idea for the image's final appearance. It's even easier when you use Adobe Lightroom presets with all of the settings built-in.

The best source for Lightroom presets is Envato Elements. It's an all-you-can-download library of creative assets you'll unlock for a flat rate. That includes thousands of the best Adobe Lightroom presets that totally re-style your images.

Envato Elements Lightroom presetsEnvato Elements Lightroom presetsEnvato Elements Lightroom presets
Elements includes unlimited downloads of Adobe Lightroom presets to help you style your images.

Let's check out just three of the preset packages included when you subscribe to Envato Elements. These are just a few of the thousands of presets you'll unlock.

1. Retrodreams Mobile and Desktop Lightroom Presets

Retrodreams Lightroom presetRetrodreams Lightroom presetRetrodreams Lightroom preset

Ready to go back in time? Then the Retrodreams Lightroom preset package might just be the perfect one for you. With brown and tan tinting and a crushed tone curve, it immediately transports your images to the days of old. Try out the 10 presets that work for both Lightroom CC and Lightroom mobile.

2. 8 Classic Ports Film Look Presets

8classic ports Lightroom preset8classic ports Lightroom preset8classic ports Lightroom preset

Every photographer needs a few "go-to" image styles. This package of eight presets is a great set of general purpose presets that you can use on a broad set of images. These are inspired by the warm Fujifilm analog styles that photographers love.

3. 20 Faded Duotone Lightroom Presets

Faded duotone Lightroom presetsFaded duotone Lightroom presetsFaded duotone Lightroom presets

Far from the ordinary, these duotone presets bring together two color tints for creative edits. There are 20 combinations of complementary colors that transform your images with just one click. Best of all, each preset is adjustable so that each effect fits your image perfectly.

More Resources to Learn Adobe Lightroom


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