How to Change Pictures From RGB to CMYK Without Using Adobe Photoshop
By Jericho McCune
RGB (Red-Green-Blue) is a color scale most commonly used by graphics-editing software to create images. The RGB color scale is the default color scale used because computer monitors use it to emit light. Unfortunately, many printing devices, such as offset-lithography, use a CMYK (Cyan-Maroon-Yellow-Black) scale for printing. Before an image can be printed, it needs to be converted into the correct color scale. Because of the high cost of Adobe Photoshop, alternative conversion methods can be used.
Download GIMP, a free, open-source graphics editing program. (See Resources.) Install GIMP by double-clicking the downloaded file and following the steps given by the installation manager.
Download the CMYK Separation Plugin for GIMP. (See Resources.) Install the plugin by double-clicking on the downloaded file.
Download Adobe ICC profiles. (See Resources.) Install them by double-clicking on the downloaded file.
Run GIMP. Open the picture that needs to be converted by clicking on "File," then "Open," and then finding the picture in the directory.
Right-click on the picture and select "Image." Then select "Separate (normal)" and accept the default destination profiles.
Right-click on the picture and select "Image," followed by "Separate," then "Save."
- When saving the image this way, a warning will appear saying that the image hasn't been saved. The image has been saved, but because the plug-in is not able to load CMYK images, the warning will continue to appear.
- Pictures converted in this manner will not be able to be edited. If future editing will be necessary, the image will need to be saved in XCF format until no further editing is required, then saved using the above instructions when editing is complete.