Respotting with the Clone Stamp
Step 18: After you sharpen any image, you should zoom in to at least 100% and then go through each section of the file, checking for spots that appeared after sharpening. Sharpening tends to enhance spots that may not have been obvious before, which is why you should double-check the spotting of your master file after any final sharpening. The procedure is the same as the spotting work demonstrated in Chapter 19: "Overall Color Correction." Do another File/Save (Command-S) to save your final spotted file.
Step 19: You can see many vivid colors on the computer screen in RGB or Lab that won't print in CMYK on a press. If you are working in RGB to send your final output to a film recorder and color transparency film, you can get more colors on film than you can on a press. If your final output is some Web or multimedia presentation, you can also get the colors there. You need to realize that each different type of computer monitor or digital color printer, or even press and paper combination, usually has a different color gamut. The gamut of your output device is the range of colors it can actually print. For more information about these issues, see Chapter 14: "Color Spaces, Device Characterization, and Color Management." If you are going to print this file on a press in CMYK, or if you are using View/Proof Colors to soft proof RGB output devices, you might want to check your out-of-gamut colors and see if you need to correct them. This might be a good time to review the discussion of View/Proof Colors and View/Proof Setup in Chapter 15: "Photoshop Color Preferences, Monitor, Scanner, and Printer Calibration." Choose View/Proof Setup/Working CMYK for now as we go through this discussion. Now choose Select/Color Range, and then choose Out of Gamut from the Select pop-up at the top of the dialog box. Click OK to see a selection of all the colors that you can see in RGB, but which won't print exactly the same in CMYK or on your RGB device when Proof Setup is set to soft proof for an RGB output device. Choose View/Extras (Command-H) to hide the edges of this selection.
Figure 20.41 Step 19: In Color Range, selecting out-of-gamut colors. Notice that we have set the Selection Preview to Grayscale so we see a large preview of the out-of-gamut colors in the image area behind the dialog. Play around with the other Selection Preview choices as you might find them useful.
Step 20: Some out-of-gamut colors, like red, often look quite different, and usually muted, when printed in CMYK. In many other colors, you might not notice the difference. Turn View/Proof Colors on (Command-Y) for an estimate of what the image will look like when printed in CMYK while you are still working in RGB or Lab. If you made the red barn really bright, you will notice it fades a bit. View/Proof Colors is on when there is a checkmark to the left of it in the menu bar. How many other changes did you see in the image? The sky might look a bit duller. Now choose View/Gamut Warning (Command-Shift-Y), and all these out-of-gamut colors will change to gray or whatever color you have set in Preferences as the gamut warning indicator. Remember that you have a selection, which you made using Color Range, of all the colors that are actually out-of-gamut. With Gamut Warning on, you can use this selection in conjunction with the Hue/Saturation command to fix much of the gamut problem. Colors often are out-of-gamut because they're too saturated. Choose Command-U for Hue/Saturation and move the Saturation slider to the left. Notice that the Gamut Warning areas get smaller the more you desaturate the selected out-of-gamut area. You might want to desaturate your out-of-gamut colors in several stages, or use the Sponge tool from the Tools palette, so you don't further desaturate colors that have already come back into gamut. To desaturate in stages, move the Saturation slider to the left, to 10. Choose OK and then choose Select/None. Now go back to Color Range (see step 19), and choose the new smaller set of out-of-gamut colors. Reduce the saturation on these, also, by 10. Continue this iterative process until you have no more out-of-gamut colors, or until the out-of-gamut areas are so small they won't show.
Step 21: Gamut Warning is a very useful tool for seeing colors that are going to be difficult to reproduce in CMYK, or on your RGB output device when soft proofing to an RGB device. However, if you always desaturate all your colors so that no Gamut Warning areas show up, you may end up with duller colors on press or your device than you would have gotten if you were a little less strict about desaturating all your RGB colors. I compared two conversions to CMYK of this image. The first had been pre-adjusted, via steps 19 and 20, to remove out-of-gamut colors, and the second was of the same image without the out-of-gamut adjustments. The pre-adjusted image didn't change much at all when converted to CMYK, which is good. The image that I hadn't pre-adjusted for out-of-gamut colors did change and got a little duller, as with the red barn, but overall was a bit brighter and more vivid in CMYK than the pre-adjusted image was. So if you work in RGB and use bright colors, even out-of-gamut ones, you might get brighter color results by going ahead and converting these to CMYK. You know that some bright colors may get a bit duller, but you can deal with those dull or changed colors when you are in CMYK mode, instead of dulling them ahead of time by desaturating based on Gamut Warning and possibly desaturating them too much. Do some tests to see what works best for you! When printing on an RGB device, like the LightJet 5000, you might find you lose a few less details in your extreme saturated areas if you bring things into gamut with the device a bit, before sending a file to the printer. Again, you should experiment and see.