What is color management?
Color management is a process that helps achieve the best possible color match between your images on your monitor and your images in the printed book.
Most people don’t have to worry about color management
Overall, your book is likely to print just fine without a color managed workflow. If anything, spend a little time slightly brightening your images as most tend to look a bit darker when printed.
However, if you’d like to take time to learn more the advantages of a color-managed workflow, read on.
What does color management require?
- Colorimeter software and hardware, such as those made by Spyder or Datacolor
- A monitor that you've calibrated with your colorimeter
- Blurb's ICC color profile
- Adobe® Photoshop®
The basics: RGB does not equal CMYK
The printed image can't perfectly correspond to the digital version. One reason is that we capture images in red, green, and blue (RGB) but we print with cyan, magenta, yellow, and black ink (CMYK). Color management helps to produce a more consistent color match in spite of this difference. It also shows which colors are likely to shift when printed.
All digital images are RGB color files. There are many varieties of RGB color spaces, including sRGB and Adobe RGB, and each can display colors slightly differently. sRGB is the more common color space and is usually the default for most digital cameras.
On the other hand, most "output devices" (like printers) use 4 ink colors--cyan, magenta, yellow, black or CMYK--to produce colors. As with RGB, there are a variety of CMYK color spaces.
The pixels of a monitor are composed of RGB elements. Accurately viewing digital images requires a monitor that has been properly calibrated with a device called a colorimeter. More info regarding calibrating your monitor can be found at X-Rite or Datacolor.
RGB to CMYK Conversion
RGB and CMYK Spaces Compared. Some colors in RGB do not have an exact equivalent in CMYK. There are often colors that we see on our monitors that cannot be reproduced perfectly on the printed sheet.
When a digital image is printed, its RGB values are converted to CMYK values for the printer. This conversion will produce unexpected color shifts if not done in a controlled and predictable manner. Overlay RGB and CMYK color spaces (see image above) and you’ll see that colors in RGB do not always have an exact equivalent in CMYK.
This means there are often colors that we see on our monitors which can’t be reproduced perfectly on the printed page. Color management, therefore, is a process by which we pick the best possible CMYK color to match a given RGB color.
What is a color profile?
The color of an image may shift when converting from one color space to another, or from one device to another. A color profile shows what the colors will look like on a particular device.
The Blurb ICC Profile is based on the GRACoL2009 reference used in commercial printing, By using this color profile you can soft-proof your images to see how they will look when printed.
You can also use our profile to convert your images to a CMYK color space to eliminate the press-side conversion. This gives you more control over the images and how they will print.