Printing & Design Tips: JANUARY 2007, #66

What is Lenticular Printing?

When I was about ten I had a Batman ring that appeared to change its image when I changed my viewing angle. Since then I have seen printed eyes that wink when I move them as well as any number of other items that show dual images. What is this all about and how does it relate to printing?

These changing images are examples of lenticular printing. Lenticular printing is not to be confused with holograms, a multitude of complex processes and products created by the use of laser beams. Lenticular printing uses lenticular files that you would prepare in digital format (as you might create an image file in Photoshop and at the same resolution as you normally use for printed images; that is, 300 dpi or higher resolution). You would provide a “before” and an “after” image. Some lenticular printers produce “before,” “middle,” and “after” images. One printer even produces up to twelve separate images. Apparently, one can more successfully achieve up/down movement with this technology than right/left movement. However, if you wanted the images to move from side to side, you could design them in vertical format and than flip them sideways in the same program.

The lenticular print provider prepares special files and then prints them onto a plastic material made up of very small, tightly-spaced, half-cylinder lenses. The rear surface of this lens screen is first coated with photosensitive emulsion, and this emulsion is then exposed to a light source representing either different views of the same image (creating a three-dimensional effect) or different images altogether (creating a “flip-book,” animation effect). The image is printed in an interlaced manner, with segments of the various images alternating. The lenticules (tiny lenses) cover the alternating printed images, hiding one image while revealing another. As you shift the printed piece in your hand, the image appears to move because the lenticules block different portions of the images from view as you move the printed piece in different directions.

Lenticular printing can also mimic depth. The lenses in this case run vertically on the printed sheet, and the left eye sees one image while the right eye sees a slightly different image. Together, both eyes perceive the two images as one three-dimensional scene.

Lenticular printing, which used to be only a gimmick for use in toys, has become a powerful advertising tool. A marketer can show a before and after image or briefly show a visual display in actual sequence of how to use the product being sold. The lenticular printed sheet is also durable, so it can be mailed as a postcard and can delight the recipient by standing out from the other mail pieces.

One thing to remember with lenticular printing is that the images must be specially prepared with attention to fine detail. If the angles of the lenticules are not precise or the images they hide and reveal are inaccurate, you will not be pleased with the effect. Closely reviewing samples provided by an experienced lenticular printer can save you headaches. As always, ask for proofs from your print provider as your job progresses. When in doubt, go with traditional offset printing. Lenticular printing is a dramatic technology but not an easy one to master.

What is the Difference Between Brightness and Whiteness?

When referring to a paper stock, brightness refers to the amount of light the sheet refects back to the viewer. On a scale of 1 to 100, a sheet with a 96 brightness would be brighter than one with a brightness of 92.

In contrast to this, whiteness refers to the quality of light reflected back to the viewer. Is it blue-white (a brighter-appearing white) or yellow-white? Depending on your goals, you might choose a blue-white paper to bring out the coolness of the imagery, for example a snow scene. Or, if your images are of chrome and metal, you might want a warmer, yellow-white sheet. In another case, you might choose a yellow-white sheet for an antique feel.

What is Synthetic Paper?

Synthetic paper is made from a synthetic resin derived from petroleum. Although it really is a plastic sheet, it has the appearance and properties of paper made from wood pulp. It is white and opaque, like wood-based paper, and it can be printed and finished (such post-press operations as folding) just like any sheet of paper.

Why should you care? Synthetic paper is perfect for a menu, a reusable placemat, or other items that will be handled repeatedly and need to wiped down or are exposed to water. In fact, I once saw a printed sheet of this stock under water in a fish tank. This would be impossible with a paper-based printing stock. Synthetic papers are also supremely tear-resistant. ID cards or printed materials used by hikers, or indoor signs to place in schools, gyms, and locker rooms would be ideally suited for this printing stock.

Keep in mind that synthetic papers must be treated differently than wood-based papers in the printing and post-press processes, so your offset provider needs to be familiar with the properties and requirements of this stock. Involve your printer early in the production process if you're considering this unconventional paper. Also make sure your printer has experience using synthetic papers.

[Steven Waxman is a printing consultant. He teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.]