Adobe Camera Raw, also known as ACR, is a plug-in utility that works with Photoshop, Adobe Bridge, and a few other Adobe programs. It’s a kind of pre-processor that allows you to edit your photos non-destructively, meaning there’s nothing you can do to your images in Camera Raw that can’t be undone. I’ve called Camera Raw a pre-processor, because many people use it to prepare images for editing in Photoshop. But its feature set is rich enough to produce finished images without ever taking them into Photoshop. It can adjust exposure, correct contrast, enhance colors, and straighten and crop as needed. You can even adjust certain areas independently of others, correct for lens distortion, and add grain and vignetting effects. What’s more, you don’t pay a dime extra for it: Camera Raw comes bundled along with Adobe Bridge when you buy Photoshop.

Truth is, once you master Camera Raw, you’ll probably use Photoshop less. In this article, we’ll look at the basics of Camera Raw and move beyond that point to work with White Balance and tonal adjustments. And you’ll see some of the capabilities and workflow advantages of working with Camera Raw, including automatic White Balance, automatic toning, snapshots, and synchronizing images.

This article is based on Chapter 24, Adobe Camera Raw, of Photoshop CS5 One-on-One: Advanced for lynda.com.

Introducing Camera Raw

This powerful utility was originally designed to process files in your camera’s “native” raw format, but it has also been able to edit JPEG and TIFF files (again, non-destructively) for some time. Camera Raw also allows you to edit dozens of photos at once, something you can’t do in Photoshop. Any edits you make in Camera Raw are also fully compatible with Lightroom, Adobe’s other raw editing utility. As a plug-in, there’s no separate icon to double-click— Camera Raw appears as a dialog box from within either Adobe Bridge or Photoshop when you need it.

Digital SLR cameras typically have the ability to save raw files, and so do most mid-range or higher-end point-and-shoot cameras. Raw files offer a lot more latitude for adjustment than JPEG or TIFF files, making raw shooting the better choice for most situations.

Even though raw files contain a preview image that you can see on your camera’s display screen, in your computer’s operating system and in Adobe Bridge, a raw file is actually a container, not an image. Each raw file holds all of the raw (as in un-processed) data from your camera’s image sensor along with metadata describing the current settings of the camera, lens, and even its flash. Raw files are typically many times larger than the corresponding JPEG image, but they contain a lot more information. Raw files typically contain 10 - 14 bits of data, where the JPEG format can only hold 8 bits. When you process a raw file with Camera Raw, you replace the small on-board processor in your camera with the much more powerful processor in your computer.

As you edit files in ACR, you’re only adjusting a preview of what the image will look like with those settings applied. Your original image remains untouched, and your settings are stored separately as metadata. Whenever you pass the file along to Photoshop for additional editing or save a JPEG or TIFF file, Camera Raw “bakes” a fresh copy of the original image with the settings applied.

By the way, Camera Raw is updated regularly to handle new models because each camera design produces a different raw file format. In fact, there’s typically a short delay after new camera models come out, before an updated version of Camera Raw is released.

Because each manufacturer’s raw file is a proprietary format and is read-only, Camera Raw usually stores the develop settings in a “sidecar” (or XMP) file. Another option is to convert your proprietary raw files to Adobe’s DNG format. That format is a published standard, and DNG files combine the raw data and the sidecar data into a single file. You can find out more by visiting Adobe.com/dng/

Starting up Camera Raw

You start Camera Raw by opening a file into it. If you try to open a raw file with Photoshop from Windows or Mac OS, Camera Raw will automatically open to edit the file. That’s because the file is not an image yet, and you’ll use Camera Raw to make preliminary adjustments before open an adjusted copy of the file in Photoshop.

Perhaps more often, you’ll use Adobe Bridge to select one or more files that you want to edit in Camera Raw. From Bridge, you can select raw, TIFF, or JPEG files to edit. When you’re ready to use Camera Raw, there’s a subtle choice to make, and that’s where to “host” Camera Raw.

If you select File > Open (Ctrl/Command + O) , Bridge will pass the files to Photoshop, and Camera Raw will open inside Photoshop. That means Photoshop will be busy, and you won’t be able to do anything else in Photoshop until you’re done with Camera Raw.

If you select File > Open in Camera Raw (Ctrl/Command + R), Camera Raw will open inside Bridge to edit the files, leaving Photoshop free for other tasks.

You can set ACR so that it always opens in Bridge when you double-click:

1. Use Ctrl/Command + K to open the ACR preferences.
2. In the General settings: turn on check box marked “Double-Click Edits Camera Raw Settings in Bridge.” It’s in the middle of the page, in the Behavior section.

The Camera Raw Interface

When Camera Raw opens, it can appear as a floating dialog or switch to a full-screen mode. Tap the letter F to toggle between the two modes. If your screen is really small, the buttons at the bottom of the dialog will be cut off in the floating dialog mode. Toggle to full-screen mode to show the buttons.

1. Top: Tool bar
2. Right side: Settings Panels and full-color Histogram
3. Left side: A vertical film strip of images appears if you open more than one image at once. It includes the Select All and Synchronize buttons.
4. The Main image window shows the active image. The preview is fully-accurate. (If you see a yellow triangle with an exclamation mark in this window, ACR is busy updating the preview. The icon will disappear when the update is done.)
5. Output controls: Save Images, Workflow settings, Open Images, Cancel, and Done.

To increase the size of the thumbnails: Drag the vertical bar on the right edge of the thumbnail column.

Navigating in the Active Image

• The Zoom tool is active by default.
• Click in the image to zoom in
• Alt/Option-click on the image to zoom out.
• Use Ctrl/Command + zero to fit in window
• Use Ctrl + Alt + zero (Mac: Command + Option + zero) to zoom to 100%. (That’s different from Photoshop, where you use Ctrl/Command + 1 zoom to 100%. That keystroke assigns a 1-star rating inside ACR.)
• Hold the space bar and drag to reposition while you’re zoomed-in. If you’re on Windows and space bar isn’t working, click one of the numerical fields and try dragging again.

Working with White Balance

When you shoot a raw file with your camera, most of the settings that you dial in, including White Balance, are simply suggestions recorded as camera metadata—you can change your mind when you process them. The only settings that are “hard-coded” into the image are those that effect the data capture: aperture, shutter speed, ISO, focal length, and focus. Those appear in the box immediately beneath the histogram. Everything else is metadata that can be revised.

White balance is much better adjusted in ACR than Photoshop. In addition, you can adjust multiple images at once or even adjust and sync settings. With Photoshop, it’s strictly one image at a time.

1. Select several images
2. Use Ctrl/Command + R to open the ACR dialog.
3. By default, just the first image is selected; to work on all images at once, click the Select All button or use Ctrl/Command + A.

There’s actually no such thing as “white” light. Light sources have characteristic colors that would normally produce a cast in your photos. Daylight occurs in varying shades of blue, while tungsten bulbs are typically yellowish. Those colors are specified by the color temperature scale, which ties each temperature (measured in a unit called Kelvins) to a specific color. The color temperature scale comes from Physics, and from the point of view of graphic designers, the numbers are backwards: high color temperatures represent cool hues and low color temperatures represent warm hues.

White balance compensates for the color of the light source by adding complementary colors to the image. That neutralizes the color cast. When the light source is yellow/orange (low color temperature, e.g. tungsten lights and candles) it adds blue, and when the light source is blue (high color temperature, e.g. daylight and electronic flash) it adds yellow/orange. There’s a practical implication in the Temperature slider: it flips the color temperature scale so that moving the slider toward a higher value makes the image warmer and moving the slider toward a lower value makes the image cooler.

The Temperature and Tint controls represent two ranges of complementary colors that slice through the color wheel at right angles to each other. Combining the two makes it possible to neutralize essentially any light source. People typically refer to the two poles of the Tint slider as Green and Magenta, but they’re actually not those specific hues. The two extremes are more like turquoise and pink.

When adjusting White balance by hand, you’ll typically make significant adjustments to the Temperature value, but only small adjustments to the Tint setting (usually no more than + or - 10). Some light sources are a bit more complicated. For example, most “white” fluorescent bulbs often have a lot of green, which can be neutralized with the Tint slider. The Fluorescent pre-set in the White Balance menu has a tint value of + 21, while the other presets have Tint settings of zero or + 10.

Another way of setting the White Balance is to use one of the menu presets. If you’re not sure what kind of light was prevalent, you can try different menu settings until you get a pleasing result. You can also start with a preset to get close, and refine the result by hand.

• When multiple images are selected, White Balance changes are applied to all selected images.
• Use the sliders or click in the value box and use the Up or Down arrow key to adjust the setting.
• The Up/Down arrow key increases/decreases Temperature in 50-kelvin increments
• Shift + Up/Down arrow bumps the Temperature value in 500-kelvin increments.

Using the Auto White Balance Dropper

The White Balance tool samples the color of whatever you click on and adjusts the Temperature and Tint sliders to neutralize that color. It was designed for photographers to use with a neutral gray target. They shoot a test frame with the target, sample the White Balance from the test frame, and then synchronize that setting to the rest of their images.

However, you can still use the tool effectively without a dedicated gray target. The trick is knowing what to click on.

• Tap I to activate the White Balance (eyedropper) tool.
• Click a moderately light area that should be neutral, and the tool will do the rest.

If the area that you sample is cool-toned, the White Balance tool will make the image warmer. If the area is warm-toned, the tool will cool the image. But, color temperature is ultimately a subjective adjustment and neutral color may not be what you really want, and warm-toned images are often preferable. You can always warm your image by increasing the Temperature setting by several hundred Kelvins after sampling a neutral setting, or you can click on something that you know is bluish to warm the image.

Synchronizing Adjustments

Once you’ve adjusted file, you can synchronize its settings to any number of other files. The synchronization process copies the develop settings from the active file (the one showing in the main window) to all other selected files.

1. Click Select All. The thumbnail list will show a blue outline around the active file.
2. Click Synchronize, and the sync dialog will open. To bypass the dialog, hold down the Alt/Option key down and click the button.
3. The dialog has a lot of options. When in doubt, select Settings from the menu at the top of the dialog and click Click OK to complete the process.
4. To undo a synchronization, use Ctrl/Command + Z.

After you select a group of images, clicking on a different image will activate it and deselect the rest. You can use the Select All button to reselect the rest, but you can also save yourself a step:

• To change the active image without deselecting the others, Alt/Option-click on a thumbnail or use the up or down arrow key.

Exporting JPEGs and TIFFs on the Fly

You can click the Save Images button at any time to Export image files without ever opening them in Photoshop. We’ve only touched on some of the editing capabilities of Camera Raw up to this point, and you can export or synchronize files after completing any adjustment.

Saving the settings (or not) to your sidecar or DNG files

Up to this point, all of your adjustments have been managed within Camera Raw. If you were to cancel the operation now, none of your changes would be recorded. Hover your cursor over the buttons at the bottom of the dialog to see a tool tip describing its options.

The following actions will update the XMP metadata in your DNG or sidecar files:

• Click Done to update the settings metadata and close the dialog.
• Click Open to close the dialog and open all of the selected images in Photoshop.
• Shift-click the Open Image button to close the dialog and open the selected images as Smart Objects. This will embed a copy of the raw file in your Photoshop file, so that it can be adjusted with ACR from inside Photoshop.

The following actions do not update the XMP data:

• Alt/Option - click on the Open button to open the images without saving the adjustment settings. (The button changes its label to Open Copy) This is useful for advanced techniques where you want to process the file in different ways but want to keep the previous adjustments.
• Clicking Cancel discards your changes and closes the dialog. It’s as if you never adjusted the files.

Bridge Integration

When you return to Bridge, any files that have been adjusted will show a small icon in the Content panel near the upper right corner of its thumbnail to indicate that settings have been applied.

You can see what settings Camera Raw has applied by looking for the Camera Raw section of the Metadata panel:

If you want to remove settings, Right-click (Mac: Control-click) on a file and select Develop Settings > Clear Settings from the menu that appears.

Multiple Scenarios with Snapshots

Clearing settings in Adobe Bridge is a brute-force way to manage settings. Instead of deleting settings and starting over from scratch, you can use Snapshots to store different groups of settings in a file. The feature was introduced mid-way into the CS4 product cycle. It’s very useful, though it has some rough edges.

Select one or more images in Adobe Bridge and use Ctrl/Command + R to return to Camera Raw.

Creating and using snapshots is simple:

1. Adjust your image
2. Click the Snapshots tab
3. Click the Page icon to make a new Snapshot
4. Give your Snapshots informative names ( e.g. WB 6400/+ 1)

5. Switch to another tab and make more adjustments
6. Switch back to the snapshot tab, and take another Snapshot.
7. Click a Snapshot to apply its settings
8. To change the name of a snapshot, click on the Snapshot to select it, Right-click/Control-click on it and then choose Rename from the menu that appears.

Snapshots appear in the list in alphabetical order. If you want to maintain snapshots in a particular order, start the name of each snapshot with a number. (e.g. 1-Default-WB 4800/-2).

There are some caveats to working with Snapshots:

• ** BUG ** Be sure to click on the Snapshot you want to rename first. If you have one Snapshot selected, and you Right-click/Control-click to rename a different Snapshot, ACR will apply the current settings to the other snapshot before renaming it.
• If you have multiple files selected, any snapshots you make are only stored in the active file (the one that shows up in the preview window).
• Snapshots cannot be synchronized, either. But, if you clear develop settings, the snapshots remain in the file.

Beyond White Balance: Tonal adjustments

The next set of sliders beneath the White Balance controls (Exposure through Contrast) adjust the luminance levels (the tonality) of the image.

Exposure and Blacks, respectively, are rough equivalents to the White Point and Black Point in Photoshop’s Levels command. Brightness is roughly equivalent to the Gamma setting in Levels. If you’re a photographer, you may appreciate that the Exposure setting is measured in f-stops. As you brighten the image by increasing the Exposure setting, the highlights move to the right and the middle tones spread. Decreasing the exposure setting darkens the image, moving the highlights to the left and compressing the mid-tones.

Click the underlined text marked Auto to have ACR automatically adjust the tones in an image. The Auto feature is more intelligent than Photoshop’s Auto Tone, Auto Contrast, and Auto Color commands.

Mass-editing: You can select all images in the film strip and then click Auto to adjust the tones. ACR adjusts each image independently, and does not apply the same adjustments to all selected images, as was the case for White Balance.

Evaluating your adjustments

Tap P to toggle the preview. Since your adjustments are only being applied to the preview, you can switch the preview on and off to compare the results with the original.

The Clipping Indicators are the two little triangles at the top corners of the Histogram. They change colors to show whether clipping is occurring, and in which channels.

• A white Highlight or Shadow indicator means that all channels are clipping.
• When either indicator is colored, that means one or two channels are clipping in the highlights or shadows.

Click the Highlight warning indicator or tap the O (for over-exposure) key to toggle a red overlay that shows where highlights are clipping. It shows red, regardless of how many color channels are clipped.

You can get a more detailed view of clipping by holding down the Alt/Option key as you drag the Exposure slider. When you do that, colors in the display window will indicate where clipping is occurring and which channels are clipping.

Alt/Option dragging the Exposure slider is a good way to find an optimal exposure setting, especially when the image is slightly under-exposed. Drag the slider to the right until color starts to break through, and then nudge it back until the color disappears.

There are equivalent controls and indicators for the Blacks/shadows in your image. Click the Shadow warning indicator or tap U (for under-exposure) to show a blue overlay to indicate where shadows are clipped.

Better still, you can hold down the Alt/Option key as you drag the Blacks slider for a multi-color clipping preview. The areas that appear black are clipping in all three channels, while colored areas are only clipping in one or two color channels. The colors that appear are the complement of the color channel that’s clipping.

• Red channel: Cyan
• Green channel: Magenta
• Blue channel: Yellow

As you drag the Exposure or Shadows slider, you can press or release the Alt/Option key at any time to toggle the multi-color preview.

The important thing to realize about adjusting both White Balance and tone in Camera Raw, is that ACR is working in a 16-bit color-rich editing space, and when you edit raw files, you’re working with all of the data from the camera. When you edit an image in Photoshop or edit a JPEG or TIFF in Camera Raw, you’re working with a file that has had its highlights and shadows compressed according to a response curve, and you’re typically starting out with a lot less luminance levels.

That means you’re going to have a lot more latitude to correct color and tone with a raw file in camera raw than you can in Photoshop. If you haven’t begun to shoot in raw, now is a great time to change your camera’s quality setting and start experimenting with this powerful format.