Adolf Luther, 'Zwei Brennpunkte', 1968, 2 layers of 16 square concave mirrors (in 2 sizes: 17 x 17 cm on 35 x 35 cm) mounted on a black wooden plate, with acrylic glass hood, 150 x 150 x 11 cm, Photo: setform.de, Adolf Luther, Hohspiegelobjekt, 1969, 3 x 3 semitransparent concave mirror lenses and flat mirror in acrylic glass box, 118,5 x 118,5 x 5 cm, , Adolf Luther, L+M (Licht und Materie), 1961, Black matter-object on wooden panel, pastose mass made of oil, pigment and chalk, 57,5 x 57,5 x 5,5 cm, Photo: setform.de, Adolf Luther, Materialbild (Dark matter piece), 1960, Matter of colour, chalk and pigment on cardboard, 54 x 72 x 5 cm, , Adolf Luther, Struktur für Licht (Structure for light), 1962, Eggshells, gesso, oil and pigment on wood, 54 x 54 x 10 cm, Photo: Archive, Adolf Luther, Hohlspiegelobjekt (silver blue), 1976, mixed media, 61 x 50 cm, , Adolf Luther, Adolf Luther, 1968, mixed media, 45 x 45 cm, , Adolf Luther, Adolf Luther, 1975, mixed media, each 75 cm diameter, , Adolf Luther, Hohlspiegelobjekt, 1969, 64 concave mirrors, aluminium, acrylic glass, 110 x 110 x 7 cm, Photo: Marcus Schneider, Adolf Luther, Linsenobjekt (Lens object), 1967, 25 square lenses in between glass panes, plane mirror, aluminum frame, 38 x 38 x 5,5 cm, © Archive Adolf-Luther-Stiftung, Krefeld, Adolf Luther, Hohlspiegelobjekt (Concave mirror object), 1968, 6 x 6 cm concave mirrors on black wooden plate in aluminum frame, 71 x 71 x 11 cm, Photo: Archive, Adolf Luther, Untitled (Hohlspiegelobjekt), 1967, 28 concave mirrors, aluminium, glass, wood, 60 x 60 x 9 cm, Photo: Inka Recke, Adolf Luther, Hohlspiegelobjekt, 1969 , 64 concave mirrors, aluminium, plexiglass,, 110 x 110 x 7cm, Photo: Marcus Schneider, Adolf Luther, Hohlspiegelobjekt, 1982, 122 concave mirrors, silver, , 71,5 cm x 71,5 cm, Photo: Marcus Schneider, Adolf Luther, Hohlspiegelobjekt, 1971, 8 x 3 concave mirror stripes on black wooden panel in aluminum frame, 101 x 101 x 9,5 cm, Photo: Archive, Adolf Luther, Adolf Luther, 1975, mixed media, each 75 cm diameter, , Adolf Luther, Hohlspiegelobjekt, 1969, 49 concave, square, tinted mirrors on aluminum, in acrylic glass frame with aluminium ledge and wooden panel, 95 x 91 x 8,5 cm, Photo: Sasa Fuis, Adolf Luther, Kinetisches Hohlspiegelobjekt (Kinetic concave mirror object), 1974, 5 x 5 concave mirors on 4 x 4 concave mirrors, wood, acrylic glass, electric motor, 78 x 78 x 18 cm, Photo: Marcus Schneider, Adolf Luther, Lichtharfe (light harp), 1966, Semitransparent concave mirror stripes, acrylic glass, 27 x 44.5 x 7 cm, Photo: Marcus Schneider, Adolf Luther, Sphärisches Hohlspiegelobjekt (Spheric concave mirror object), 1972, 5 concave semitransparent mirror stripes in acrylic glass box , 30 x 50 x 9 cm, Photo: Marcus Schneider, Adolf Luther, Landschaft , 1974, Mirror-Photo Collage, 28 x 51 x z cm, archive, Adolf Luther, Hohlspiegelobjekt, 1972, 3 x 13 circular concave mirrors in front of 2 x 12 circular concave mirrors, aluminium frame, glass on black wooden panel , 150 x 36,5 x 4,5 cm, Photo: setform.de, Adolf Luther, Hohlspiegelobjekt (Concave mirror object), 1974, 4 x 4 mirror objects black wooden panel in aluminum frame , 41 x 41 x 4,5 cm, Photo: Archive, Adolf Luther, Sphärisches Hohlspiegelobjekt (beleuchtet), 1979, 8 x semitransparent mirrorstripes,  1 flat mirror, plexiglass, flourescent lamp, 40 x 40 x 16.5 cm , Signature: Luther 79, Stamp: Sehen ist schön, Photo: Archiv Adolf-Luther-Stiftung, Krefeld, Adolf Luther, Spiegelobjekt mit Licht (Mirror object with light), 1974, Concave semi-transparent mirror Ø 60 cm in Plexiglas box, 62 x 62 x 16 cm, Photo: setform.de, Adolf Luther, Stehlinsen (Lens on metal foot), 1977-78, Concave mirror, semitransparent, synthetic framework, steel pole with foot, ∅ ca. 60 cm and ∅ ca. 50 cm, height variable, max. 240 cm, Photo: Archive, Adolf Luther, Stehlinsen (Detail), 1977-78, Concave mirror, semitransparent, synthetic framework, steel pole with foot, ∅ 60 cm, height ca. 240 cm, Photo: Archive, Adolf Luther, Hängelinse (Hanging lens), 1985, Concave mirror, semitransparent, synthetic framework, ∅ 50 cm x 7,5 cm, Multiple, Photo: Marcus Schneider, Adolf Luther, Lichtschleuse (light trap), 1962, Stripes of glass in between glass plates, aluminium frame, steel rack, 51 x 38 x 14 cm, Photo: Inka Recke, Adolf Luther, Sphärisches Hohlspiegelobjekt, 1990, Semitransparent concave mirror, acrylic glass, 40 x 40 x 9 cm, Photo: Marcus Schneider, Adolf Luther, Hohlspiegelobjekt, 1967, 49 square concave mirrors with chamfered edges on mirror surface , 53 x 53 x 8 cm, setform.de,