Fig. 3From: Evaluation of novel cleaning systems on mock-ups of unvarnished oil paint and chalk-glue ground within the Munch Aula Paintings ProjectMock-up set 2. The three artificially soiled, aged and bread-cleaned mock-up types (5 × 7 cm2) with cross-sections (middle) and micrographs of surfaces with a ×5 objective lens (lower). Relative surface characteristics based on visual observation are indicated below the imagesBack to article page