German painter, active in Austria. He went to Vienna in his youth and, apparently self-taught, became a portrait-painter. His earliest known work, surviving only in an engraving (1728) by Andreas Schmutzer and Josef Schmutzer, is a portrait of Graf Johann Adam Questenberg in the formal Baroque style. Subsequently, under the influence of Balthasar Denner, he turned to a more intimate style of representation, mainly in simple half-length or head-and-shoulders portraits. He was influenced by Rembrandt both directly through the study of his works and also through Jan Kupecky who worked in Vienna for a time. //