Color Management Primer: Color Settings

by Jay Kinghorn

Digital photography is in the midst of a major transition. Photographers are performing image corrections on a processed file less frequently (JPEG, TIFF, PSD), making the bulk of image corrections on an unprocessed raw file (NEF, ORF, CR2). From a workflow perspective, this gives photographers better image quality and faster processing. From a color management perspective, this new workflow allows photographers to select an ICC profile based on the output, compositing or collaboration characteristics. This is due to the increased use of camera raw files and improvements made to raw processing applications.

For example, if you use Lightroom or Aperture for processing your camera raw files, you don’t need to select a general editing space as you do with Photoshop. Instead, you select the appropriate print profile during the printing process, a different editing space when exporting photos for the Web or inclusion in a printed piece and still another ICC profile when compositing photos in Photoshop. This adds flexibility to your workflow. As camera raw processing and the selective editing capabilities of raw processors progresses, you may only have to choose an ICC profile in the export and printing process.

We aren’t quite there yet, so this article will cover how to configure color settings in the most popular imaging applications on the market today: Photoshop, Aperture and Lightroom. Regardless of your workflow, this article will help you understand why you will want to select one profile over another and why certain profiles are best suited for specific tasks.

Purpose Of Color Settings

In most image-editing applications, the color settings are used for two primary purposes:

1. Establish a baseline set of standards for the application to follow when creating a new document, previewing photos lacking an embedded ICC profile, or making a color conversion (e.g. RGB > CMYK or RGB > Grayscale).
2. To draw your attention to images containing an ICC profile different from the primary profile used in your workflow, or images that do not contain an embedded ICC profile.

Color management decisions should be made by you, not by your preferences because as smart as these programs have become, they cannot serve as a substitute for your judgment. You will want to verify that the results of any color conversion represent the colors and tones in your photos as faithfully as possible.

What matters more than understanding specific settings, is understanding the color management processes in your workflow, knowing what profile is applied to your images at each stage and, in particular, making decisions when you make color conversions as a regular part of your workflow.

To help shed light on the process, let’s quickly review the key stages of your workflow, highlighting the areas where color conversions occur.

Image Capture

Most digital photographers today shoot in the camera raw format. This provides superior quality and maximum flexibility in image processing. Since camera raw files are unprocessed files as opposed to JPEG or TIFF files, they cannot use ICC-based color management. Instead, all camera raw processing applications, like Adobe Camera Raw (a part of Photoshop and Lightroom) or Capture One, use their own method of displaying color for editing and previewing purposes.

An ICC profile is only applied when you convert the unprocessed camera raw file to a processed file type (JPEG, TIFF or PSD). Some camera raw processors, like Lightroom and Aperture, allow you to select your desired ICC profile during the export process (to JPEG, TIFF or PSD). Other programs process your photos according to a set of preferences applied to all photos.

Processed images (in-camera JPEGs, most scanned images) have color management applied from the moment the digital file is created. For JPEG images created with your digital camera, the ICC profile selected in your camera’s menu options determines whether the digital file is processed into the Adobe 1998 or sRGB colorspace. For film scans, most scanning software allows you to first apply a scanner profile (either manufacturer-created or custom-built), then convert from the scanner profile to a common editing space (ProPhoto RGB, Adobe 1998 RGB) for further processing.

Image Editing

Once your image has been processed by your camera raw software, or converted from your scanner’s ICC profile, your photo should now be converted to one of the commonly used editing space profiles. Editing space profiles have several distinct advantages over printer, scanner or monitor ICC profiles. For starters, the profiles are gray-balanced, meaning equal values of red, green or blue always equal a shade of gray. Since printer, scanner or monitor profiles reflect the color characteristics of a specific device, your monitor or inkjet printer, they are not always gray balanced.

What About CMYK?

For photographers, working in the CMYK color mode has several distinct disadvantages. First, working in any of the commonly used CMYK color spaces shrinks the color gamut of the photograph to match the smaller color gamut of CMYK printing presses, unnecessarily discarding some colors that can be printed on current inkjet printers. Second, unlike RGBediting spaces, CMYK color spaces are not gray-balanced, since equal values of cyan, magenta and yellow do not equal a neutral shade of gray. This makes it more difficult to perform color corrections. Lastly, most photographers use RGB-based output devices, like monitors, inkjet printers, or digital photo printers like the Oce LightJet. Working in CMYK requires two additional color (RGB > CMYK > RGB) conversions that can slightly degrade the quality of an image.

Therefore, the CMYK color mode is recommended only for photographs that will be reproduced on a printing press.

Display Compensation

In the previous article, I discussed the need to work on an accurately calibrated monitor. The monitor profile, created during the calibration process, is stored in your operating system and is used by programs like Photoshop to ensure the RGB values displayed on screen accurately represent the colors in your digital photo. This process, called display compensation, converts on the fly, the RGB values of the pixels in your photo from your editing space used for performing corrections, to your monitor profile. Display compensation allows a given photo to appear the same on your monitor and mine, even though we’re using different monitor types, makes and models. The brilliance of this system is that the conversion takes place automatically and does not require any attention or action on your part.

Output

As you prepare your image for output to the Web or for printing, you will typically need to convert your photo from your editing space to a profile better suited for the output medium. Often, this will be a printer profile created to reflect the color characteristics of the printer, paper and ink combination in use. I’ll help you select, use and even create printer-specific ICCprofiles in part IV of this series.

When preparing images for the Web, you’ll want to first convert colors to the sRGB color space before posting them online. Although color managed Web browsers are slowly gaining ground, most Web browsers do not use ICC color management and as a result, the colors in your photos will appear differently to each user. Converting to sRGB helps to preserve the integrity of your photo across all Web browsers.

Adobe RGB

sRGB

Simulation showing the change in colors that occurs when a photo in the Adobe 1998 color space is displayed online in a non-color managed browser.

The conversion between your editing space and output profile can take place within your imaging application or in the printer driver.

What editing space should you choose?

Before we jump into this discussion, I wanted to provide a quick definition of terms. An editing space is a specific class of color profile designed to be used as an intermediate image processing colorspace. As such, editing spaces are mathematically created instead as opposed to the standard method of measuring the color characteristics of a specific device.

There is no single best editing space for all photographers to use. Instead, you will want to select an editing space that contains a color gamut large enough to contain the colors you encounter in your photographs and encompasses the color gamut of your intended output.

Let’s apply this abstract concept to a few real world scenarios.

• A photographer shooting mostly portraits doesn’t need a large color space since the range of colors in his work (skin tones) are not highly saturated and fit easily within the color gamuts of even the smallest profiles.
• A professional landscape photographer capturing highly saturated colors and reproducing her photos on an inkjet printer and commercial printing press will need an editing space with a larger color gamut. Because her work contains vivid colors, and her output mediums can reproduce many of those colors she needs to select an editing space with a larger color gamut than either of her output methods.
• A conceptual artist blending multiple photos together into heavily-saturated, rich compositions needs to use an editing space encompassing all the possible output mediums available today and in the foreseeable future. Because his work is sold as limited edition prints, and is incredibly time-consuming, he needs to work in the largest editing space available.

No single editing space works equally well for all three photographers. Instead, each photographer needs to select the editing space best suited for their workflow.

Characteristics of Adobe 1998, sRGB, ProPhoto RGB

Let’s look at the characteristics of the three most popular editing spaces, Adobe 1998, sRGB and ProPhoto RGB and begin developing recommendations for each of these three photographers. As you read about each of these color spaces, keep in mind that the more work you perform in a camera raw processing application the more your editing space decision will be based on your output medium and less on your style of photography.

Adobe RGB 1998

Perhaps the most versatile, and arguably best-suited color space for digital photography, Adobe RGB 1998, more commonly referred to as Adobe 1998 is large enough to contain all the colors reproducible with a standard printing press and most of the colors that can be printed with a professional-level inkjet printer.

There are a few naturally occurring reds and greens, which can be captured by a digital camera but fall outside the color gamut of Adobe 1998. This is one of the reasons, some photographers use ProPhoto RGB as their primary editing space. For most photographers, the advantages of Adobe 1998 make it a sound choice for an all-purpose digital photography workflow, particularly those who reproduce their photos on inkjet printers and printing presses.

sRGB

Probably the most maligned of all editing spaces, many photographers shun sRGB for it’s limited color gamut. While it is true, sRGB has a significantly smaller color gamut than Adobe 1998, sRGB is useful as an output space for images destined for the Web and as an editing space for wedding and portrait photographers who do not require a large color gamut for their work.

Many of the online print fulfillment services and digital photo labs prefer to receive image files in the sRGB color space since most digital minilab machines are not built to understand color management. Photos sent in the Adobe 1998 color space appear washed out and desaturated when printed on these machines. For this reason, wedding and portrait photographers using these services should consider converting photos to sRGB before delivering files to their printing service or using sRGB as their primary editing space.

ProPhoto RGB

Of the three most commonly used editing spaces, ProPhoto RGB contains by far the largest color gamut. This is an attraction for archivists and fine-art photographers who need to preserve all the colors in their original raw file or scan in a processed format.

Although working in a large-gamut color space offers some advantages, the disadvantages associated with this color space make it unsuitable for many photographers for two primary reasons.

• Requires 16bpc Images: working in ProPhoto RGB requires you acquire your scans, or export your photos from your camera raw processor in 16 bits per channel (bpc) if you plan to apply additional corrections to your images. ProPhoto RGB contains such a large color gamut, you run the risk of posterizing, creating unnatural transitions in your image, with simple corrections. Working with 16bpc photos eliminates this problem, but forces you to work with significantly larger file sizes. For some, this is an acceptable tradeoff, for others it slows the workflow considerably.
• Larger Than Your Monitor’s Color Gamut: few photographers today are working on wide-gamut monitors, capable of displaying most of the Adobe 1998 color space. Instead, the standard monitor’s color gamut is similar to that of sRGB. When working with Pro Photo RGB there are many possible color values that lie well outside the sRGB color space and are impossible to see on a standard monitor. This means that when working in ProPhoto RGB, photographers are making edits to colors they cannot see. Unless one is accustomed to making subtle color edits “by the numbers”, it is difficult to take full advantage of the larger color gamut ProPhoto RGB offers.

For these reasons, I recommend ProPhoto RGB only for expert users who clearly understand the benefits of working in a wide-gamut color space. For most other users, I recommend using Adobe 1998 as your primary editing space.

A Workflow Note

Undoubtedly, some will be surprised by the recommendation of Adobe 1998 over ProPhotoRGB for everyday use. From a strictly technical perspective, ProPhoto RGB is a superior choice for image processing, but from a workflow perspective, Adobe 1998 is simpler, safer and more widely accepted. As camera raw processing, display, computer and printing technology improves, the benefits of ProPhoto RGB may be more applicable to a wider audience.

When this occurs, I suggest going back to your original raw file and re-exporting it using the latest camera raw processor into a large-gamut space. I can guarantee the results you get from future raw processors will be superior to the results you see today.

If you are performing a limited edition fine-art run, or are investing a large amount of time retouching or compositing a photo, use ProPhoto RGB on a 16bpc image. For the rest of your everyday work, use Adobe 1998 and 8 bit images. You’ll have a faster workflow today and can always return to the raw image when a specific need arises.

Color Settings In Adobe Photoshop

Of the commonly-used applications, Photoshop has the most convoluted structure for setting color management preferences. This is, in large part, due to Photoshop’s age, and role as an image editor for a variety of different uses, from medical imaging to web design. In this section, I’ll help you configure Photoshop’s Color Settings and show you how to handle the Profile Mismatch and Missing Profile warning dialogs.

Because Photoshop is used for correcting processed image files (Adobe Camera Raw handles the raw files), Photoshop needs to use ICC profile to display an image correctly Most often, it will use the ICC profile currently embedded in the photo. If an image doesn’t have an embedded ICC profile, Photoshop needs to rely on the Color Settings preferences to display the photo. Photoshop also uses the Color Settings when making color mode changes in the Image>Mode menu or when creating a new document.

Photoshop’s Color Settings dialog is found under the Edit menu (Edit > Color Settings) on both Mac and Windows. In earlier versions of Photoshop, Color Settings were found under the Photoshop menu on Mac computers.

Most versions of Photoshop use the North America General Purpose 2 color setting preset. This uses sRGB as the primary editing space and hides the color management warnings. This is a sensible default given Photoshop’s wide audience, but isn’t ideal for digital photographers. I recommend changing the color setting to the North America Prepress 2 preset. This uses Adobe 1998 as the RGB editing space, referred to as the Working Space in Photoshop, and activates the color management warnings, which will help identify any images in your workflow which are not color managed or use an ICC profile that is different than your primary editing space.

Should you need to make additional adjustments to the Color Settings policy, to select a specific CMYK profile for example, simply choose the ICC profile from the appropriate menu (RGB, CMYK or Grayscale). If your ICC profile is not visible from the pull-down menu, click on the More Options button on the right side of the dialog box for an expanded list of color profiles and additional color management options. I recommend leaving the Conversion Options and Advanced Controls at their default settings.

For a detailed explanation on each of the options in the Color Settings dialog, I recommend the excellent Real World Color Management by Bruce Fraser, Chris Murphy and Fred Bunting.

Profile Mismatch & Missing Profile Dialogs

After adjusting Photoshop’s Color Settings, you may begin to see two color management-related dialog boxes when you open files. The Profile Mismatch dialog indicates the file you’re opening contains a different embedded profile than specified in your Color Settings preference, while the Missing Profile dialog tells you that the photo you’re opening does not contain an embedded ICC profile.

Profile Mismatch

As long as an image contains an embedded ICC profile, Photoshop will use it for displaying the colors in your photo correctly. The profile mismatch warning is nothing more than an indicator that the embedded profile in your photo differs from your Color Settings. You can continue to work with the photo as-is, or, if you want to standardize your workflow on a specific profile, you can convert the photo to your working space profile. This will prevent the Profile Mismatch dialog from appearing in the future.

With either scenario, select the “Use the embedded profile” option (instead of the working space option). If you would like to convert the photo from the existing profile to your Working Space, you’re best served using the “Convert To Profile” command (see illustration below) after the photo is opened.

Missing Profile

This warning is a bit more of a cause for concern than the Profile Mismatch dialog when working with RGB files. The Missing Profile dialog indicates that there is no ICC profile embedded within this photo and therefore, Photoshop does not know how to display the RGBvalues in the photo correctly. In other words, the appearance of colors in the photo are ambiguous. Your best bet is to choose the “Leave as is” (don’t color manage) option from the dialog and use the “Assign Profile” command to assign a profile to the photo, bringing it into a color managed workflow.

When Photoshop opens a photo that does not have an embedded ICC profile, it uses the Working Space profile to preview the colors in the photo. This may cause the colors and tones in the photo to shift undesirably. Your first task in Photoshop is to use the Assign Profile command (Edit > Assign Profile) to select the correct ICC profile for this photo. Using the image preview, experiment with different color spaces until you find one that gives a “correct” look to the image. Since the photo did not have an embedded ICC profile, you’re essentially left to “guess” the correct color profile for the photo. To expedite the process, begin with sRGB, then Adobe 1998 and ColorMatch RGB. Once you’ve found the correct profile, you may wish to convert it to your Working Space to standardize your workflow.

Convert To Profile

Whenever performing a color conversion, you’ll want to use the Convert To Profile dialog (Edit > Convert To Profile). Here, you have full control over the conversion options and are given a preview to predict the effect the color conversion will have on your photo.

In the “Convert to Profile” dialog, choose your the profile you’re converting to in from the Destination Space pull-down menu. Set the Conversion Options as shown in the screenshot. This will give you the most accurate color conversions for the broadest range of images.

Tip: Why Two Steps?

With both dialogs, I recommend deferring your decision to convert to the working space, or assign a specific profile until after you’ve opened your photo in Photoshop, instead of performing these tasks within the initial dialog. Although this adds an extra step, it provides you with a preview to see how these changes will affect your photo. Whenever you’re performing a color conversion, or changing the way Photoshop handles your color, it benefits you to check the preview to ensure the appearance of your photo does not change.

The color management options available when printing from Photoshop will be covered in the next article.

Adobe Lightroom

Compared to Photoshop, the color management options in Lightroom are far simpler. Lightroom does not have Color Settings preferences as is found in Photoshop. Instead, Lightroom is hard-wired with a group of sensible defaults. Lightroom uses a modified version of ProPhoto RGB for processing your camera raw files, sRGB for generating Web galleries and honors the embedded ICC profile for any JPEG, TIFF or PSD images brought into your Lightroom Library.

In this setup, you have only two color management decisions to make: the profile used when opening photos into another application, like Photoshop, and the profile you’d like images converted to when exporting them from the Library.

Edit In Presets

When opening an image from Lightroom into another application, Lightroom uses the color profile specified in the “Edit In” presets to when processing your camera raw files for delivery to other applications.

Lightroom’s preferences are found under the Lightroom menu on Mac and the Edit menu on Windows. Select the External Editing tab and choose your desired profile in the Edit in Photoshop and Additional External Editor sections. Here, you can also select the bit-depth and file format you’d like used when integrating Lightroom with other applications.

When Exporting photos from your Lightroom library, you can select the ICC profile you’d like your photos converted to in the File Settings portion of the Export dialog.

The color management options available when printing from Lightroom will be covered in the next article.

Apple Aperture

Aperture is structured in much the same way as Lightroom. Your camera raw editing and previews use a modified version of the ProPhoto RGB color space. Processed images with embedded ICC profiles are honored. Your only real control over the color management options within Aperture, aside from printing, is during the Export process.

When Exporting versions of your original files, you are prompted to select one of Aperture’s Export presets. These can easily be customized for your workflow. In the Export dialog File > Export > Versions, select Edit from the Export Preset pull-down menu. In the resulting Export Presets dialog box create a preset with your desired file type, image size, image resolution, bit depth and ColorSync profile. Be sure to check Black Point Compensation to preserve shadow detail. This will create a temporary preset for one-time use. To permanently store your present, click on the ”+” button in the lower-left corner of the dialog to create a new preset.

Other Imaging Applications

Today, photographers are using dozens of different applications for image processing, file management and camera raw processing. It is impossible for me to go into detail for each one in this article. Instead, I’ll leave you with a few guidelines.

• Establish a color management standard for all processed files in your workflow. This will facilitate the exchange between applications thereby minimizing the number of color conversions necessary to execute your workflow.
• Designate one application for your camera raw processing. Each camera raw processor interprets your camera’s raw files in slightly different ways. Further, adjustments made in one camera raw application can rarely be read by another. For these reasons designating one camera raw processor as your primary application for raw files will make your workflow much simpler.

Conclusion

Most imaging applications today are ICC-compliant and, with the information provided in this article, should be easy to customize to match the specific color management policies you’ve established for your workflow.

In the next article, I’ll help you take control of the printing process and help improve the match between what you see on screen and your finished print.

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