These are the ICC profiles that the program uses to interpret the documents to be processed. You can select them from the Properties sections. The input profile of the selected document must match the profile that has been used in the designing program as the output profile. If these two profiles differ, there can be differences in the interpretation of colors and therefore in the printed result.
Each design program (CorelDraw, Illustrator, PhotoShop, etc) allows specifying the color profile with which the created design will be saved or exported. This is the profile that has to be selected in Input profiles.
They can be added to the program by clicking on the square button on the right. In case a design comes from an unknown source and the profile with which it has been generated is not specified, the most usual work profiles are; RGB: Generic RGB or CMYK: Generic CMYK
Take into account, though, that by selecting those profiles the result is not guaranteed.
NOTE: When a TIFF, JPG or EPS image is loaded in the program, and one of the profile lists indicates "Embedded...", it means that the ICC profile that comes embedded in the file will be used. They are usually images coming from Adobe® Photoshop® 5.0.2 or higher. In these cases, it is not necessary to select the input profile since the program recognizes them automatically.
Proofing consists of obtaining from our printer the results which would be obtained using another printing system. Through different Rendering intents, we specify to the color engine what calculations need to be made in order to transform colors from one working space to another, taking into account both origin and target working spaces. There are four main rendering intent groups.
- Perceptual or photographic: with this rendering method the whole working space of origin is uniformly scaled with respect to the origin of coordinates until it fits the destination working space.
- Saturation: this method is done in two steps. The first is like the perceptual one when the working space of origin is scaled down until it fits into the destination one. In the second step the working space is expanded, and the points that delimit it meet with the edges of the working space of the destination.
- Relative colorimetric: when there are different color temperatures between working spaces, the relative intent detects this variation and equals both spaces before comparing them. This method is used when we wish to dismiss the color of the paper or media.
- Absolute colorimetric: again, when there are different color temperatures between working spaces, the system will ignore this fact and will try to compare colors as it finds them. This rendering method is used when we want to take into account the color of paper or media, and what it does is subtract that color from the image color, and then we obtain the desired color when printing. Logically, the precision of the result will depend on the exactness of the color profiles we use.