This Month's Topic: Alphabet Soup: RGB-to-CMYK Conversion

RGB-to-CMYK conversion is a snap in Photoshop: In the Image menu, select Mode, then check CMYK Color.

The quality and simplicity of digital cameras allow anyone to take professional-looking photos. However, digital image files are not as “plug and play” as cameras - especially when you’re ready to place those photos into your book.

Photos from a digital camera – as well as those taken from a scanner, CD-ROM or website – are almost always created in RGB color. “RGB” stands for red-green-blue, which are the three colors of light that are used to display color on a monitor. The inks used in printing presses use a different color space, CMYK, which represent the four “process” ink colors that combine to create printed images. Your image files must be converted from RGB to CMYK color in order to be reproduced on press.

The Conversion Process
The tricky aspect of RGB-to-CMYK conversion is that RGB images look fine on screen and when printed on a desktop printer. However, RGB images will not yield color separations at the prepress stage, and thus cannot be used for printing.

To convert your images in Adobe Photoshop (version 6.0 or later), go to the Image menu and select Mode. In the dropdown Mode menu, select “CMYK color”. The process will be similar for other image editing software programs.

Important Note – Keep in mind that PDF files will need to be resubmitted if they contain RGB images, as color space conversion cannot be performed in Acrobat.

Planning Tip – Request hard proofs for color-critical applications: At IGI Publishing, our monitors are calibrated with our printing equipment to ensure seamless color representation from screen to paper. However, the time and cost to perform this calibration places it beyond the reach of most self-publishers. That exposes one of the limitations of proofing images on screen: The displayed color may not be an exact match for the printed piece, even after you’ve converted images to CMYK.

For color-critical applications, such as the cover of your book, you may want to request a hard proof from us. This will offer you the most accurate representation of color, giving you the peace of mind that your published book will have the same color as the proof.

The IGI Publishing Solution
IGI Publishing wants to make the publishing process easier for you. Our experienced, dedicated prepress and layout team can perform as much or as little photo editing as you need – including RGB-to-CMYK conversion. From layout and typesetting to printing, binding and beyond, let IGI Publishing be your single publishing resource.