Today’s Question: When you see a large amount of out-of-gamut color on an image (like most of the reds on a male vermillion flycatcher), should you just let the software figure out how to bring them into gamut and is that what the proof setup shows, or should one adjust something (and, if so what) to bring the colors into gamut?
Tim’s Quick Answer: In general, the software you’re using for printing will do a good job of converting the colors based on the output limitations. However, you may want to consider a different print configuration, or to apply some adjustments to compensate.
More Detail: Today’s question is a follow-up to a recent question about previewing what a print will look like on your monitor display via the soft proofing feature that is available in Photoshop and Lightroom Classic. In particular, it relates to the Gamut Warning feature that is available in Photoshop but not Lightroom Classic. This is an overlay that indicates which areas of an image contain colors that cannot be produced accurately with the intended printer, ink, and paper combination.
When you print a photo that has out-of-gamut colors, the colors that are out of gamut will automatically be shifted to a color value that can be printed. With the Relative Colorimetric setting for the rendering intent, any out-of-gamut colors will be shifted to the closest printable value. With the Perceptual setting, all colors in the image will have their saturation reduced to the point that out-of-gamut colors can be printed. I generally prefer to use Relative Colorimetric because it maintains the accuracy of most colors in the print.
Many printers use a single set of inks, and so the real variable (other than using a different printer) is to consider different papers. For example, a glossy paper will generally have a color gamut that is quite a bit wider than with an uncoated matte paper. So, if you find significant areas of the photo are out of gamut with a particular matte paper, you might consider a semi-gloss or glossy option instead.
You can also apply adjustments to the image to try to compensate for color that are out of gamut. However, this can often lead to unintended consequences. For example, you could shift the hue of the reds so they are perhaps a bit more orange, bringing them back into gamut. However, that can also lead to a situation where the color fidelity is obviously wrong, and worse than would have been achieved by simply letting the software manage the colors as part of the printing process.
