Dye Sub Printers Explained
Dye sublimation printers (also known as "Dye Diffusion Thermal Transfer Printers") are known for their high quality photographic output. As the technology continues to be improved, dye sublimation printers are bringing cost-effective high quality digital printing into the mainstream. Consumers can even purchase a desktop dye sublimation printer for under $900.
How Do Dye Sublimation Printers Work?
Dye sublimation printing starts with films that contain dyes. This will either be a single four layered film with cyan, magenta, yellow, and gray pigments or four separate films for each color. Because the films contain the pigments, they will appear red, blue, green, and gray.
During the printing process, the films are placed on the paper and heated up by the print head. This will cause the pigments to leave the film and enter into the paper where it cools re-solidifies. This is the "sublimation" part. Sublimation means to heat something and turn it into a vapor, then to form it back into a solid. Because the pigments go from solid, to gas, and back to solid, there is little mess compared to ink.
What Makes A Dye-Sub Printer So Good?
There are two factors that contribute to the quality of dye sub printers. The first is continuous tone, and the other is un-dithered color.
The color produced by a dye-sub is the result of the mixing of pigments to get the actual color. This is in contrast to most other printing methods which use a tight group of colored dots which, when seen by the human eye from a distance, appear to be a color (a process known as "dithering"). Under magnification, the dots are clearly different colors, and when seen close up with the naked eye the picture appears grainy. Because only one color needs to be printed (instead of up to four), a dye sub can place more dots on a paper. It takes a 1200 dpi printer to get the resolution a 300 dpi dye-sub printer is capable of.
Another difference that helps is that because the color sublimes on the paper instead of being laid down as little dots, the edges of each pixel are blurred. This gives the impression of blending for a more natural appearance. Dots from an inkjet leave large white gaps in between pixels, giving the impression of a grain.
Since longevity is something we all want from our photographs, it's also comforting to know that because dyes sublimate into the paper instead of just being painted onto its surface, dye sub prints tend to resist fading and are often colorfast. Using special dyes and papers allow them to last even longer.
Why Doesn't Everyone Use Dye Sub Printers?
For one thing, dye sub printers are typically far more expensive then comparable inkjet printers. You can buy a photo quality printer for half of what a comparable dye sub printer costs at the consumer level. On the professional level, the gap is much closer, but they can still be as much as a thousand dollars more expensive.
Dye sublimation printers also only do one thing well: photo quality full color images. They are neither practical for document printing nor are they as fast as inkjet printers. A dye sub printer takes about a minute to produce a print regardless of whether it's a full color photo or a page of typed text because it still has to print each pixel thermally. An inkjet printer will only print the areas that need to be printed, so it can produce a full page of typed text in seconds. On the other hand, to produce a photographic quality print, an inkjet printer can take up to 10 minutes.
When it comes to printing on different kinds of papers, a dye sub is limited to papers and films. An inkjet printer can print to just about anything you can run through it, including cotton canvas, envelopes, cardstock, and foam backed presentation board.
Inkjet printers are more versatile, and since most people print both photographs and documents, they accept the trade-offs. Until recently, when low cost digital cameras and powerful computers became available to the general public, the only people who truly needed dye sublimation printing were photography studios, print houses, and art departments.