Type of media makes a difference
The type of print media is one of the most overlooked variables in printing. How a printed image looks is directly affected by the color, brightness, finish, coating, opacity, weight and absorbency of the media on which it’s printed.
Different substrates
If your job is printed on a substrate with different color or brightness than the proofing substrate (also called a white point, color cast or paper shade) the press sheet will not look like the proof. For example, if the white press stock has a blue shade, the print will look blue compared to the proof. And if the press stock has a yellow shade, the press sheet will look more yellow than the proof; see the penguin images. Differences in paper color or brightness will tend to be more noticeable in lighter tones and clean, pastel colors.
Understanding UV
Many of today’s papers are enhanced with Optical Brightening Additives, or OBAs, to make them appear brighter. OBAs typically consist of materials which fluoresce under UV wavelengths. This causes issues in color measurement and color management. For example, UV enhancers sometimes make the paper appear more blue, but only in certain types of lighting. Most UV-based additives fade upon exposure to light, in some cases causing paper to change color after just a few days. This affects the color of the printed piece. Ironically, printed images typically look very similar on brightened and non brightened papers when viewed apart from each other, even though they look different adjacent to each other. The selection of paper is a crucial factor in accurate color reproduction.
