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Correcting Camera Raw Images
The images that many modern digital cameras are capable of producing can be nothing short of breathtaking. Yet by the time a photo leaves a digital camera and enters an image-editing program such as Photoshop, even the highest-quality JPEG can be many steps removed from its original splendor. That’s because the camera itself almost always performs a slew of processes meant to make the image more presentable. These can include white-balance adjustments, color and brightness correction, and sharpening and compression passes over an image. Although it may look brighter, more balanced, and sharper by the time you open it, you’ve actually lost a lot of the original information. And for professional digital photographers and graphic designers, every last pixel counts.| Photoshop | Luckily, all hope is not lost. Many midrange and high-end digital cameras now offer the option of saving your images as Camera Raw files, which skip the postprocessing and save a perfect, pristine representation of the exact image captured. It’s akin to a digital negative. Sometime after the release of Photoshop 7 but before Photoshop CS was unveiled, Adobe quietly introduced a plug-in for the program that was capable of opening and making adjustments to certain Camera Raw files. With the release of Photoshop CS, a phenomenally expanded version of the Camera Raw plug-in now ships with the program. When you work directly with Camera Raw files, you have access to better image detail and a wider range of colors than would be available otherwise. For professionals who need to get the absolute most out of their digital images, this is nothing short of a godsend. |
As I mentioned in Chapter 3, Camera Raw files are proprietary, meaning that each manufacturer adheres to a different and unique format. As I write this, Photoshop supports Camera Raw files created by a number of cameras from Canon, Fujifilm, Leaf, Minolta, Nikon, and Olympus. Additionally, Adobe has pledged to continue expanding support to more manufacturers and models over the life of the product. Check www.adobe.com to see any recent additions to the list.
| Cross-Reference | The Camera Raw dialog box is a professional-level tool, which is why I cover it in obsessive detail in the Photoshop CS Bible, Professional Edition. Don’t feel like you’re missing out on all the action, though. In this section and the two that follow, I cover the basic stuff you need to know to get up to speed with Camera Raw. |
Instead of the gigantic, unmanageable files you might expect them to be, Camera Raw files are actually smaller than uncompressed TIFF images, and Adobe’s Camera Raw dialog box can make adjustments at an impressive speed. The only way to access the Camera Raw features in Photoshop CS is to open a file saved in a Camera Raw format. Instead of displaying the image, Photoshop brings up the massive Camera Raw dialog box, as shown in Figure 17-43.
Figure 17-43: Think of the new Camera Raw dialog box as a one-stop color correction laboratory for your uncompromised digital photos. Here, I’m adjusting an image captured with an Olympus E-1 digital camera.
Along the bottom of the Camera Raw dialog box are various settings you can adjust to determine how your image will take shape when brought into Photoshop for regular editing. You can set the color space of the image, the number of bits per channel, and even the size and printing resolution of the image. Naturally, Photoshop cannot create image data where none exists, so choosing an image size greater than the size at which the image was originally captured simply interpolates the pixels as though you’re using the Image Size command. The real power of the Camera Raw feature, however, lies in the image-adjustment options in the panels on the right side of the dialog box.
Making color adjustments
As you can see in Figure 17-43, the Adjust panel in the Camera Raw dialog box is comprised of two sections: settings for adjusting white balance and settings for adjusting the tonal qualities of an image. White balance information is recorded when an image is shot and saved as metadata in the Camera Raw file. Photoshop CS’s Camera Raw dialog box uses these settings as the default whenever it opens an image. The White Balance section of the Adjust panel gives you two options:
Temperature: This setting lets you modify the color temperature of an image, in a similar manner to the new Photo Filter command discussed earlier in this chapter. Increase the Temperature value (which is measured in Kelvins) to bring out the more yellow and reddish colors in the image; decrease the Temperature to cool the image into the realm of blue.
Tint: The Tint slider adjusts and compensates for different color tints that the image may contain. Drag the slider to the left to increase the amount of green in the image and drag it to the right to remove green and add magenta values.
You can also select a preset from the White Balance pop-up menu, located above the Temperature slider. Choosing any of these settings adjusts both the Temperature and Tint sliders to account for various lighting conditions present when the image was first shot.
| Tip | You can also set the white balance manually by selecting the white balance tool (it’s the eyedropper located at the top-left corner of the dialog box) and clicking a spot in the image that you’d like to assign as white or neutral gray. The White Balance settings in the Adjust panel snap into a position that adjusts the selected pixel to white and adjusts the other pixels in the image accordingly. |
Below the White Balance settings are five sliders that let you make adjustments to the tonal qualities of an image:
Exposure: Quite simply, the Exposure setting adjusts the brightness of the image. If you noticed that the Adjust panel also contains a setting called Brightness, you’re probably wondering, “What gives?” The Exposure slider is based on the F-stop of a camera and adjusts in much larger increments than the Brightness setting. In fact, adjust this value more than a little and you’re bound to encounter some clipping, which occurs when pixels are pushed to pure white or black and lose all detail. It’s best to increase this setting until it’s just about to clip, ramp it down a smidge, and then do your finer brightness adjustments with the Brightness slider.
| Tip | Alt-drag (Option-drag on the Mac) the Exposure slider triangle to see a dynamic depiction of any and all clipping pixels in the image. |
Shadows: Increase this value and watch as more and more pixels get sucked into darkness and, eventually, pure black. It might appear as though the Shadows slider is just upping the contrast in the image, but it’s really performing a function that’s more in line with the black point slider in the Input Levels section of the Levels command, discussed earlier in this chapter.
Brightness: As I mentioned, this setting makes gentle adjustments to the general brightness levels of the image.
Contrast: This setting increases (higher values) or decreases (lower values) the contrast in the midtone colors of the image.
Saturation: This is your basic saturation option that we’ve encountered a number of times before. Decrease the value to –100 to remove all colors from an image; increase the value to +100 to get colors so vibrant you may need to close your eyes. Watch out.
Sharpening and smoothing
Click the Detail tab to access options you can use to adjust the sharpness and smoothness of a Camera Raw image. Shown in Figure 17-44, the Detail panel contains the following three settings:
Figure 17-44: The Detail tab in the Camera Raw dialog box allows you to sharpen a dull image or reduce the scattered particles in a noisy one.
Sharpness: The Sharpness slider works in much the same way as the Unsharp Mask filter, which I discussed in Chapter 10. The biggest difference lies in the fact that the Camera Raw dialog box does not give you controls for Radius or Threshold. This is due to the fact that Camera Raw calculates these factors for you using information based on the camera model and the ISO (or light sensitivity) for the image. Instead of cranking up the Sharpness value in the Camera Raw dialog box, it’s often a better idea to perform all your editing to the image in Photoshop and then apply the reliable old Unsharp Mask filter as a final step.
Luminance Smoothing: This slider adjusts the amount of blurring that the Camera Raw dialog box applies in an attempt to reduce grayscale noise in an image. Depending on the ISO and general quality of the camera, a little bit of noise — those random speckles that lower the quality of an image — is common. Increase this setting to smooth out some of the noise, but don’t go overboard — too much smoothing and you’ll lose valuable detail in the image.
| Note | The Camera Raw dialog box fully supports multiple undos through the usual keyboard shortcut, Ctrl+Alt+Z (z -Option-Z on the Mac), so don’t be afraid to experiment. |
Color Noise Reduction: This slider performs the same function as Luminance Smoothing, except it works towards decreasing the amount of colored noise artifacts in the image.
| Tip | Although Photoshop CS can open a number of Camera Raw image file formats, it’s not capable of saving the image back to the Raw file after you’ve adjusted it. Rather, you need to save in a format such as PSD, TIFF, or if you’re working with an extremely large image, Photoshop’s new PSB file format. There is a workaround, however, if you’d like to quickly save your adjustments with the Camera Raw file. After you finalize your settings, hold down the Alt key (Option key on the Mac) until the OK button turns into an Update button. Click this button to update the metadata of the Camera Raw file to reflect your settings. Although you haven’t altered any pixels in the file, the settings you’ve specified will reappear the next time you open the image. |
If you have a series of Camera Raw images all shot under the same circumstances or with the same camera, it would seem redundant to have to adjust the settings for each file. Luckily, Photoshop CS’s Camera Raw function allows you to save specific settings as templates and apply them to other Camera Raw files. Simply click the right-pointing arrowhead next to the Settings option, and choose Save Settings from the resulting pop-up menu. This creates a template that you can later access by choosing Load Settings from the same pop-up menu. You also can choose Set Camera Default, which automatically assigns the current settings as the default settings when you open a Camera Raw image.
