RGB Working Spaces

Make sure the Color Management Policies pop-up menus are all set to Preserve Embedded Profiles; otherwise, you just might want Photoshop to warn you when opening an image or when pasting. If you turn off all three checkboxes at the bottom of the Color Settings dialog box, you'll want to look for a “#” or “*” in the title bar of your image once you open it. A “*” indicates an image with a profile that does not match your RGB working space, while a “#” indicates an image that is untagged (missing profile). If you want to see how the RGB Working Spaces relate to the range of colors that can be reproduced on different printers, visit www.digitalmastery.com/color.

The RGB working spaces include the following:

• Adobe RGB: The best general choice for people who end up printing their images on desktop inkjet printers or send them to commercial printing presses.

• Apple RGB: A less-than-ideal choice because adjustments won't affect the image evenly from light to dark. Useful if you have old images that didn't use color management, which will be talked about later.

• ColorMatch RGB: Not a bad choice for images that will end up on a commercial printing press, but not quite as ideal as Adobe RGB for that purpose.

• ProPhotoRGB: Ideal for photographs that are scanned in 16-bit mode from color transparencies, because it offers a very wide range of colors. Can cause posterization in 8-bit images.

• Monitor RGB: Use when you'd like your images to look identical in both Photoshop and your Web browser. An alternative to sRGB, but it does not take into consideration what other people will see when viewing your web site.

• sRGB: Good for people who create Web graphics and would like to limit the colors used in their images to those that can be seen on an average user's screen. Less than ideal for anyone who will end up printing on a commercial printing press (but is okay for newsprint) or photographic process because it has such a limited range of colors available.

Now that we've gotten our RGB working space out of the way, let's make sure that our images will be friendly to others. We'll do that by including a profile of our working space with each image we create. That way when someone else opens it, their copy of Photoshop will know what colors of RGB the image was made from, so it can display it properly. When you save an image, make sure the Embed Color Profile check box is turned on (Figure 7.11). That will “tag” the image with an ICC profile.

If you don't tag your images, Photoshop will ask you to guess which colors of RGB the image was made from when you re-open the image (Figure 7.12). If you guess wrong, the image won't look like it's supposed to. I get a lot of untagged images, but I really don't like the way Photoshop makes you blindly choose a profile without seeing the consequences. If you get an untagged image, here's what I suggest you do: Just choose the Leave As Is option and then click OK. Then, immediately after opening it, choose Assign Profile from the Edit menu in CS2 or the Image > Mode menu in CS. Then try the top four choices listed under the profile pop-up menu (just make sure the Preview check box is on). Each time you change that setting, you should see your image change. Keep cycling through until you find one that makes your image look good. The person who sent you the image didn't include enough info for Photoshop to know what the colors should look like, so you're just guessing. And, no, it's not worth calling the person who sent it to you because they obviously don't know enough about color management to have it set up correctly, so you'll just end up confusing them by asking which setting to use.

At this point in the chapter, I'm assuming that you haven't messed with any color-management settings except for the ones we've discussed. If you aren't seeing any mismatch warnings, then turn on the three check boxes that appear at the bottom of the Color Settings dialog box.