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Fotothek df tg Optik Strahlenoptik Reflexion Brennspiegel Hohlspiegel Parabolspiegel. Scan Deutsche Fotothek dftg color MIKCenter Berlin GmbH Kupferblatt Nr Bamberg Brennspiegel Papier Kupferstich cm Optik Strahlenoptik Reflexion Brennspiegel Hohlspiegel Parabolspiegel Spiegel ppnX Druck Deutsche Fotothek gefrdert von