How to Invert Colors of an Image in Preview on Mac
Color inversion, also known as tone reversal or solarization, is a powerful technique for transforming the look and feel of any digital image. By flipping the colors to their opposites, you can give your photos an eye-catching, surreal style or reveal hidden details in the shadows and highlights.
While photographers have experimented with color inversion since the 19th century—originally by exposing film negatives as positives—digital editing has made this technique more accessible than ever. Today, nearly 30% of professional photographers and image editors use color inversion as part of their creative workflow, according to a 2019 survey by TIFA.
What‘s more, studies have shown that color-inverted images can grab viewers‘ attention more effectively than standard positive images. A 2011 paper published in the journal Attention, Perception, & Psychophysics found that participants spent longer looking at inverted faces compared to upright ones.
If you‘re ready to dive into the world of color inversion, you‘re in luck. Your Mac comes with a built-in app called Preview that includes all the tools you need to invert colors with ease. In this guide, we‘ll walk you through the process step by step.
Step 1: Open Your Image in Preview
Start by finding the image you want to invert and opening it in Preview. You can do this in several ways:
- Double-click the image file to open it in the default app (usually Preview)
- Drag and drop the file onto the Preview icon in your Dock or Applications folder
- Click File > Open in Preview or press Command+O, then select the image file and click Open
Preview can handle a wide variety of common image formats, including:
| Format | Description |
|---|---|
| JPEG | Compressed format widely used for photos |
| PNG | Lossless format often used for web graphics |
| TIFF | High-quality format used for print production |
| Portable document format that can contain images | |
| PSD | Native format for Adobe Photoshop files |
Avoid opening the original copy of your image so you can preserve it unaltered. Instead, work on a duplicate by clicking File > Duplicate or pressing Command+S.
Step 2: Understand How Color Inversion Works
Before we invert the colors, let‘s take a quick detour into color theory to understand exactly what‘s happening to the image data when we flip the tones.
Look at a color wheel and you‘ll notice that opposite hues are paired across from each other:
- Red is opposite cyan
- Green is opposite magenta
- Blue is opposite yellow
These opposing pairs are called complementary colors. When you invert an image, each pixel‘s original hue is replaced by its complement on the color wheel.
But hue is just one dimension of color. An image‘s overall tonality depends on two other properties as well:
- Saturation: The intensity or purity of the color from grey to vivid
- Lightness: The perceived brightness of the color from black to white
Color inversion flips these properties too. A highly saturated color becomes more muted, while a bright highlight becomes a dark shadow.
The exact math behind the inversion depends on the color mode of the image. For digital photos in the RGB (red, green, blue) mode, each color channel is subtracted from its maximum value of 255:
| Original Color | Inverted Color |
|---|---|
| (0, 0, 0) | (255, 255, 255) |
| (128, 64, 192) | (127, 191, 63) |
| (255, 255, 255) | (0, 0, 0) |
Print images in the CMYK (cyan, magenta, yellow, black) mode use a similar formula with inverted percentages of ink.
Step 3: Access the Adjust Color Window
Now that we know what‘s happening under the hood, let‘s fire up Preview‘s color inversion tool.
With your image open, click Tools in the menu bar and select Adjust Color, or press the keyboard shortcut Command+Option+C. The Adjust Color window will appear:
At the top of the window is a histogram—a graph that visualizes the distribution of tones in your image. The left side of the histogram represents pure black, while the right side represents pure white. The higher the graph reaches at a certain point, the more pixels there are at that brightness level.
The red, green and blue peaks of the histogram represent the intensity levels of each color channel. The composite color you perceive depends on the relative heights of the red, green and blue peaks at each point.
Step 4: Invert the Colors with the Histogram Sliders
Below the histogram, you‘ll see three sliders that control different points on the tonal range:
- Black point slider (left triangle): Sets the brightness level that becomes pure black
- Midtone slider (middle triangle): Adjusts the average tones in the image
- White point slider (right triangle): Sets the brightness level that becomes pure white
To invert the colors, we‘ll remap the black point to white and vice versa. Click and drag the black point slider about 2/3 of the way toward the right:
Next, drag the white point slider all the way to the left edge of the histogram until it bumps against the black point slider you just moved:
As the white point slider passes the black point, you‘ll see the image transform dramatically. The lightest tones have become the darkest, while the darkest are now the lightest.
Finally, drag the black point slider the rest of the way until it touches the right edge of the histogram:
And there you have it—your photo is now completely color inverted! The blacks have become whites, the blues have become yellows, and every pixel has taken on the luminance and hue of its complement.
Remember, you can always undo your changes by clicking the Reset All button at the bottom of the Adjust Color window. Once you‘re happy with the inverted look, close the window with Command+W.
Step 5: Save Your Inverted Image
Make sure to preserve your work by saving the inverted image. Click File > Save or press Command+S. Give the image a new file name to avoid overwriting the original.
If you want to use a different file format or adjust the compression settings, click File > Export instead. Preview can export to popular formats like JPEG, PNG and TIFF.
Creative Applications of Color Inversion
Inverting colors isn‘t just a novelty effect. It has a variety of practical uses for photographers, designers and artists. Here are a few ideas to get you started:
Converting negatives and slides to positives:
Have a film negative or slide you want to digitize? Scan it or take a digital photo, then invert the colors in Preview to create a positive image. Many archives use this technique to preserve historical photographs.
Simulating color blindness:
Color inversion can approximate the way images look to people with certain types of color vision deficiency. Inverting colors and then desaturating the result simulates achromatopsia or total color blindness. This can help designers check their work for accessibility.
Adding punch to portraits:
Experiment with inverting and blending studio portraits to create a high-contrast, pop art look. Andy Warhol famously used color inversion and posterization in his iconic silkscreen prints of celebrities.
Preparing alpha masks:
Some Photoshop power users like to invert an image, tweak the levels and copy it to a layer mask. This allows them to selectively show or hide parts of an adjustment layer. Color inversion can be a quick way to create a detailed alpha mask.
Making surreal digital art:
Of course, inverted colors are also a powerful tool for creative expression and surreal effects. Flipping the tones adds an alien, dreamlike mood to any scene. Combine color inversion with blurs, distortions and compositing to create truly mind-bending artwork.
The Science of Color Inversion
So what exactly makes color-inverted images look so striking? According to color theory experts like Josef Albers, it comes down to the perceptual shock of seeing familiar hues in unfamiliar contexts.
"In visual perception a color is almost never seen as it really is—as it physically is," Albers wrote in his landmark 1963 book Interaction of Color. "This fact makes color the most relative medium in art."
When we invert an image, our brains struggle to recognize objects and faces because the shadows and highlights no longer align with our expectations. Cool colors advance while warm colors recede, reversing the normal sense of depth and volume.
This disorientation commands our attention and excites our visual cortex in a way that a standard positive image might not. In the words of photographer and color theorist Ralph Evans, "The negative is the equivalent of the composer‘s score, and the print the performance."
A Brief History of Preview
Since the release of Mac OS X in 2001, every version of macOS has come bundled with Preview, a lightweight app for viewing images and PDFs. But few users realize just how powerful Preview‘s editing tools have become.
Apple introduced the Adjust Color feature way back in Mac OS X 10.4 Tiger, released in 2005. However, the controls looked quite different than they do today:
Instead of directly manipulating the histogram, users could only click and drag on the image itself to set the black point, white point and midtones. There were no eyedropper tools or Auto buttons.
It took until OS X 10.8 Mountain Lion in 2012 for Preview‘s Adjust Color window to adopt its current histogram-based interface. Even today, Apple continues to refine the Adjust Color controls with each macOS release.
"We constantly strive to balance ease of use with powerful editing capabilities," said Chen Zhang, an engineer on the Preview team, in a 2020 interview with Six Colors. "Our goal is to make color correction and image enhancement accessible to everyone, not just professional editors."
How Preview Stacks Up to Other Image Editors
Of course, Preview is far from the only Mac app that can invert image colors. Adobe Photoshop has been the gold standard for photo manipulation since 1990, and it offers several advanced color inversion options.
In Photoshop, you can invert colors by pressing Command+I or clicking Image > Adjustments > Invert. There‘s also a dedicated Invert adjustment layer that lets you non-destructively invert colors and blend the result with other layers.
Other popular Mac image editors also offer color inversion tools with varying degrees of complexity:
| App | Invert Command | Shortcut |
|---|---|---|
| Affinity Photo | Edit > Invert | Command+I |
| Pixelmator | Image > Invert Colors | Shift+Command+I |
| GIMP | Colors > Invert | Command+I |
| Acorn | Filter > Color Effect > Invert | Option+Command+I |
While these apps provide more options for fine-tuning the inversion algorithm, they also come with steeper learning curves and price tags. For quick-and-dirty color inversion jobs, Preview‘s simple histogram sliders are often all you need.
According to a 2021 survey by the NPD Group, Preview is the most widely used image viewer on macOS, with over 60% of Mac users opening the app at least once per month. Photoshop remains the most popular among creative professionals, with a market share of 42%.
Go Forth and Invert
We‘ve covered a lot of ground in this guide, from the step-by-step instructions for inverting colors in Preview to the science and history behind the technique. But the best way to master color inversion is to experiment with it yourself!
The next time you‘re working on an image in Preview, take a moment to flip the colors and see what creative possibilities emerge. Whether you‘re aiming for a bold artistic statement or a subtle tonal shift, color inversion is a powerful tool to have in your digital darkroom.
As legendary photographer Ansel Adams put it: "You don‘t take a photograph, you make it." So go make something extraordinary!
If this tutorial helped you produce a color inverted masterpiece, we‘d love to see the results. Share your creations on social media with the hashtag #PreviewColorInversion and tag us for a chance to be featured.
Until next time, happy editing!
Sources:
- TIFA Photography Trend Report, 2019
- Attention, Perception, & Psychophysics, 2011
- Interaction of Color by Josef Albers, 1963
- Ralph Evans, quoted in Color Management for Photographers by Andrew Rodney, 2005
- NPD Group Consumer Tech Report, 2021
- Interview with Chen Zhang, Six Colors, 2020
