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Problems with rendering intent, embedded profiles, or a pesky magenta cast in your prints? Here are some tips and tricks to help understand and smooth the process for better printing and less headaches.

By Justin Sherry

Preserving an Embedded Profile

Some people feel that by converting their image to a larger color space (sRGB to Adobe 98) they will increase the color in their file. This is not true. Converting to a different color space takes the values from one color space and reprocesses them (as best as possible) to the new color space.

Ironically, this conversion usually results in colors slightly more muted than the original, even though it is now in a larger color space. This is due to a loss of data during the conversion process.

To give an example, it’s like taking a 10-oz. glass with five ounces of water, and pouring it into a 12-oz. glass, while spilling a little bit of water during the process. The end result is a bigger glass (color space) with slightly less water (color data) than you had to begin with. If you are unsure about your current Color Management Policies, they can be found by pressing Shift+Ctrl+k on a PC or Shift+apple+k on a Mac.

The Right Rendering Intent

The answer to which rendering intent you should use depends on the file. The two preferred for printing photographic images are Perceptual and Relative Colorimetric.

Perceptual is typically preferred for photographic prints on luster or gloss papers. This setting helps preserve smooth gradations when transitioning from one color to the next.  One example of this would be the transition from light blue to dark blue in a skyline photo. If this setting is used on a matte surface the appearance may appear a little flat.

Relative Colorimetric will give you more saturation, which is especially noticeable on matte media (fine art papers, matte canvas, and so forth). The downside to using this is in a photographic image with any gradation (like the skyline image mentioned above), because it will suffer from what’s known as posterization. This intent is usually best suited for images without any gradation, typically fine art reproductions.

The only real way to tell which intent to use is to soft proof your images before you print. To do this in Photoshop, go to View>Proof Setup>Custom. Within the Customize Proof Condition window you can select your output profile along with the appropriate rendering intent and black point setting.

As long as the preview box is checked, you will be viewing your image through the eyes of the output profile while taking into account rendering intent and black point compensation. Try all four combinations to see which one gives you the best results for your image (Perceptual and Relative Colorimetric/Blackpoint Compensation on or off).

Miscast Magenta

There are two common reasons why some prints may have a magenta cast (besides clogged nozzles). As long as you maintain a tightly color-managed workflow, both of these can be eliminated.

1. Wrong Source Space Profile – If your Color Management Policies are set to anything other than Preserve Embedded Profile, you run the risk of misrepresenting the color data in the file. As long the images coming from your camera are tagged with their respective color space and you are always preserving the embedded profile, you will always have a properly color managed workflow.

If you are unsure whether or not your images are tagged, go to Color Settings and check the box labeled Missing Profiles: Ask when Opening. Then, open an image straight from your digital camera. If a dialog appears and says, “The document does not have an embedded RGB profile,” it is not tagged, so Photoshop doesn’t know which color space the file was created in.

Most cameras that don’t tag the images usually capture in sRGB. However, check the owner’s manual for your camera to be sure. If you confirm that your camera doesn’t tag the image, find the color space your camera does capture in, and make sure it is your RGB working space in Color Settings.

2. Double Color Management – This is quite common when people use a custom profile for the first time. When using Epson media, the printer’s driver typically does all of the color management for you. Also, Photoshop defaults to allowing the printer determine color management.

However, when using any third-party media with a custom profile, you must let Photoshop control the color management by selecting the profile in the Print with Preview screen. This is also where you apply the appropriate rendering intent and black point settings. Since Photoshop is doing the color management, you must make sure you tell the Epson driver not to. To do this, select the following:

On a PC – When in the driver, on the main tab, select Advanced. In the Advanced screen, in the upper-right corner labeled Printer Color Management, select Off (No Color Adjustment).

On a Mac – When in the driver, go to the third drop-down from the top (this usually defaults to Copies & Pages) and select Printer Color Management. In this menu, select the button labeled Off (No Color Adjustment).

Whether you're working on a Mac or a PC, if you do not turn off Printer Color Management both Photoshop and the print driver will be doing their own color management, resulting in a double-color-managed print. The end result is typically a very strong magenta cast.

Justin Sherry is LexJet’s technical support specialist.