http://www.kunsthaus.ch/en/the-collection/conservation/examples-from-the-world-of-art-conservation/max-ernst/removal-of-the-added-coats-ofcolor-and-varnish/removal-of-the-added-coats-of-color-and-varnish-mechanical-removal-of-the-non-original-layers/?redirect_url=title%3DDirection

Kunsthaus Zürich

Removal of the added coats of color and varnish

Film still 2:  Mechanical removal of the non-original layers
Film still 2: Mechanical removal of the non-original layers