Dye Sublimation printing

For many years dye-sublimation printers were specialist devices widely used in demanding graphic arts and photographic applications. The advent of digital photography led to the technology entering the mainstream, forming the basis of many of the standalone, portable photo printers that emerged in the second half of the 1990s.

The printing process used by true dye-sublimation printers differs from that of inkjets. Instead of spraying jets of ink onto a page as inkjet printers do, dye-sublimation printers apply a dye from a plastic film. This takes the form of a either a roll or a ribbon, similar to that used by thermal wax printers, usually containing consecutive panels of cyan, magenta, yellow and black dye.

The transfer film passes across a thermal print head consisting of thousands of heating elements. The heat causes the dyes on the film to sublimate that is, turn from a solid to a gas without a liquid phase in between and the gaseous dyes are absorbed by the printing paper. The amount of dye actually transferred is controlled by varying the intensity and duration of the heat.

When the ink is absorbed by the paper it tends to diffuse, blurring the edges of. This diffusion helps the printer create continuous tones of colour as a result of the ‘dots’ of ink blending together. The effect is most pronounced in relation to the direction in which the paper is travelling, since the movement of the paper enlarges the area that the ink is applied to.

Dye-sublimation printers employ a three-pass system, layering cyan, magenta and yellow dyes on top of one another. They then add a clear coat to protect the print against ultraviolet light. Whilst this is capable of producing excellent results, it is far from economical. Even if a particular image needs practically none of one of the pigments, that ribbon segment is still consumed. This is why it’s common for packs of paper for use with dye-sub printers to contain a transfer film capable of producing the same number of prints.

The new generation of Samsung and Canon printers using this technology give fantastic results and offer a quality of print usually associated with traditional Silver Halide photos from large processing labs and very often for much the same cost

The Myth about Resolution
As dye sublimation printers can produce this continuous tone output, there is no need for them to print at much higher resolutions to fool the human eye (unlike inkjet). This means that a 300dpi image on a Dye Sublimation Printer is equal to 4800dpi on an Inkjet Printer. A 400dpi image is equal to 6400dpi on an Inkjet Printer

Dye-sublimation differs greatly from inkjet in many ways; most significantly in quality. Dye-sub is known for its high quality and continuous tone output.
Continuous tone means that all gradations of colour are used when creating an image. For example, when creating a grey scale, from black to white, a continuous tone printer will show all shades of grey in between the black and the white by actually printing them.

A half-toning device such as an ink-jet printer will use a dithering technique of placing dots close together in order to trick the eye. In other words, ink jet printers use a series of black dots placed close to white dots in order to trick the eye into blending the pixels when viewed. With magnification the difference can be seen where the dye-sub output is clear and sharp, but dots can be seen on ink-jet prints

So will dye-sublimation replace inkjet printing. I doubt it, as most users will want a printer that will multi-task. However, if its just photographs you want to print, then there is no better option. At the end of the day its up to you.