Illustrated Glossary: Satellites

Satellites are particles or droplets of colorant that lie outside the intended dot shape or text in either electrophotographic or inkjet prints. In electrophotography, whether dry or liquid, toner is applied and adheres to the charged area of the photo-conducting drum or belt. During this process, some toner may land outside of the intended area of the image forming dot or text. It is then permanently fused into place during the final steps of printing. With dry toner this can be rather dramatic

In liquid toner prints, satellites are more rare and look like small, individual spots.

In inkjet, droplets ejected from the print head nozzles sometimes break apart into large primary drops with smaller drops trailing behind. Sometimes the trailing drops will land on the same spot as the primary drop and go unnoticed. If the trailing drop follows a different trajectory, however, it can land adjacent to the main dot creating a satellite. Because this phenomenon affects image quality, printer manufacturers have worked hard to eliminate the problem. As a result newer inkjet prints will show fewer satellites than those printed many years ago.