Selecting the right paper for your magazine

Folio: The Magazine for Magazine Management, Annual, 1994 by Alex Brown

Defining paper quality, whether recycled or conventional, depends on defining your magazine's needs.

Printing salesmen like to draw little triangles on their pads to inform you, the print buyer, that their plants will provide the best of "price, quality and speed." They tend to acknowledge the lack of harmony among these three attributes, but vow to juggle them with aplomb. You want all three ingredients perfectly balanced: You want to pay just enough for just the right level of quality on just the right schedule.

One way to become more precise and practical with definitions of quality is to emphasize the function it has in a specific publication. Consider paper: You may be surprised to learn that the grading system for coated paper is based on the single criterion of brightness. This is an excellent anchor for a scale because it measures paper's reflectance, which is going to govern the contrast of printed ink and, a little more subjectively, the brilliance of an image. But to be called a Number 4, a sheet must simply meet the blue light reflectance standard of 73 percent to 79 percent. How it gets there isn't standardized, although that can matter to you, the buyer. Working with paper grade alone is applying a single definition of quality.

A look at paper properties

Besides brightness, paper has some measurable properties with significant visual impact. The focus here is on those that affect print quality with the broadest strokes--although nearly every aspect of a sheet's structure, manufacture and content has some effect. With recycled paper, for instance, you may encounter strength problems compared with conventional, and its degree of smoothness can vary as well. A paper's appearance can be evaluated by its brightness, whiteness, gloss, smoothness and opacity. Without plunging too deeply into manufacturing, you should also make note of a paper's pulp type and its formation characteristics.

* Brightness is measured on a tester that determines a paper's capacity to reflect a particular blue wavelength; reported as a percentage.

* Whiteness is often confused with brightness, but it's an entirely different property.

Brightness measures the reflectance of blue light; whiteness treats the evenness of reflectance of all colors in the spectrum. The brightest paper may reflect a great deal of blue and very little red or green; the whitest papers tend to have much lower reflectance readings, but maintain equal color reflectance--making them neutral backdrops for ink. Finally, the highest reflectance papers may achieve this by reflecting little blue but much of both red and green.

* Gloss is defined by a paper's specular reflection of light rays. Our eyes determine it by noting how shiny or lustrous a paper appears. Extensive calendering or other surface treatments cause a paper to move toward optical flatness--the point at which light rays striking it are reflected back in parallel rays, as they would be from polished glass. At the other extreme, matte finish papers reflect light with great diffusion, scattering the rays in all directions. Publishing and advertising both set great store by high gloss because it tends to work hand in hand with brightness to make printed images sparkle. High gloss actually adds to color intensity by increasing the gloss contributed by the ink itself.

However, gloss for gloss's sake is a dangerous route toward beautiful printing. We see printed color by looking at light reflected through ink by paper. A glossy surface sends the majority of light straight back at us, but it's also busy showing us how much light is falling on it.

* Smoothness is bound up with gloss and another key characteristic, paper formation. Smoothness is what it sounds like, but that doesn't mean it feels like what you may anticipate. Silky finishes and sizings may make a paper feel sumptuous, but smoothness is specifically the levelness of a sheet, which includes its internal evenness. Paper fibers can be compressed from the outside into obedient height, but if the fibers, formation characteristics, and basis weight of the paper require it, this compression results in pockets of greater fiber density. Smoothness isn't tested with a finger tip, but with an air-leak tester that measures the rate at which air passes through the sheet. Formation and smoothness can be examined by looking through a sheet to see how evenly translucent it is, and whether dark or light pockets appear.

* Opacity usually figures in any production decision involving quality. For some magazines, opacity can be sacrificed in pursuit of both greater brightness and lower cost: the move to a lower basis weight of a higher brightness sheet can impart an appearance of higher quality. But opacity, the extent to which light transmission is obstructed, does not come solely from paper weight or caliper. The chief ways to increase opacity are by adding fillers or dyes; by relying on the high light absorption properties of groundwood pulp; by limiting pulp bleaching to maintain a darker and more light-absorbent fiber; and by positioning the paper toward the blue-white, high brightness end, because blues, greens and grays absorb more light than do yellows and reds.