The artists of the so-called "Pioneer Group" made the step towards a full exploitation of the possibilities of the red-figure technique. They were active between "circa" 520 and 500 BC. Important representatives include Euphronios, Euthymides and Phintias. This group, recognised and defined by twentieth-century scholarship, experimented with the different possibilities offered by the new style. Thus, figures appeared in new perspectives, such as frontal or rear views, and there were experiments with perspective foreshortening and more dynamic compositions. As a technical innovation Euphronios introduced the "relief line". At the same time new vase shapes were invented, a development favoured by the fact that many of the pioneer group painters were also active as potters.