Convex and Concave (1955)

Convex and Concave (1955)
Artist: M. C. Escher
Dutch
Lithograph


Convex and Concave is a lithograph print by the Dutch artist M. C. Escher, first printed in March 1955.
It depicts an ornate architectural structure with many stairs, pillars and other shapes. The relative aspects of the objects in the image are distorted in such a way that many of the structure's features can be seen as both convex shapes and concave impressions. This is a very good example of Escher's mastery in creating illusion of "Impossible Architectures". The windows, roads, stairs and other shapes can be perceived as opening out in seemingly impossible ways and positions. Even the image on the flag is of reversible cubes. One can view these features as concave by viewing the image upside-down.
Note that all additional elements and decoration on the left are consistent with a viewpoint from above, while those on the right with a viewpoint from below: hiding half the image makes it very easy to switch between convex and concave.(Wikipedia)

Hand with Reflecting Sphere (1935)

Hand with Reflecting Sphere (1935)

Artist: M C Escher
Dutch (1898 - 1972)
Lithograph


Maurits Cornelis Escher (17 June 1898 – 27 March 1972), usually referred to as M. C. Escher, was a Dutch graphic artist. He is known for his often mathematically inspired woodcuts, lithographs, and mezzotints. These feature impossible constructions, explorations of infinity, architecture, and tessellations.(Wikipedia)

Escher and the interior of his studio in Rome are reflected in the mirrored sphere that he holds in his hand. Escher's preoccupation with mirrored reflections and visual illusion belongs to a tradition of northern European art established in the fifteenth century.