PERFORMANCE ASSESSMENT FOCUS

Within the CELL, this Performance Assessment is designed to:

• promote problem-solving skills by encouraging students to find appropriate solutions to problems.
• encourage group collaboration to demonstrate their combined knowledge and lab skills to solve perspective and symmetry problems.
• assess students’ understanding of the concept of mirror image.

Perspective and Symmetry in Art

In Investigations One through Three, students examined the concept of perspective. Artists use perspective to represent landscapes, cityscapes, and portraits with objects in the background.

Perspective and Vanishing Point

During these first three Investigations, students learned that the further an object is placed in the distance, the smaller that object will appear in a painting. This is chiefly achieved through the use of vanishing points. In addition, students learned that by overlapping objects, artists can simulate the order of objects we observe in their paintings. An excellent example of several of these principles of artistic perspective is shown in the Edgar Degas painting, The Ballet Class, below:

Look at lines 1, 2, and 3 as well as the persons A, B, and C. Line 1 touches the shoulders of the closeup dance with her back to us (A). It then does the same for the instructor (C) and the distant dancer (B). Next, follow Line 2, which passes roughly through the midsection of each of the three individuals, and Line 3 which runs to the vanishing point along the feet of all three. This results in progressively “smaller” individuals as their position is removed further and further from the foreground. Notice also, the insert (D), which reproduces dancer B‘s actual size in relation to dancer A. look how much smaller she is! Yet, in the painting, dancer B appears to be approximately the same height as both dancer A and instructor C. Such use of perspective gives Degas’ painting both depth and interest.

Finally, the placement of figures A, B, and C causes them to overlap with other portions of the picture. The instructor (C), for example, is placed in front of the group of dancers near the door on the left, and dancer A is in front of the piano, and the dancer seated atop it.

Other Aspects of Perspective

Artists can also portray depth and distance in their work through color and detail. Generally, warm colors appear nearer, while cooler colors appear more distant from the foreground. Notice that in the illustration below, the artist has even separated the paint on her palette by their warmth.

In addition, when great distance is represented, there is usually a loss of sharp details as the perceived distance from the foreground increases. One of the most famous paintings of all time, Leonardo da Vinci’s Mona Lisa, clearly uses color and loss of detail in the background landscape behind his subject (below).

Among the many artists that achieved fame during the Rennasance, perhaps no other artist exemplified the close ties between science and art as Leonardo da Vinci. One of the reasons his portrats look so life-like is that he dissected dozens of human cadavers and studied muscles, skeletons, nerves and other important details of human anatomy. Two pages from some of his many journals are shown below.

Look at the skeletal system images on the lefthand journal page above. Such dissections and drawing studies enlightened Leonardo regarding the underlying anatomical structure to support the outward appearance of the human form.

Bilateral Symmetry and Mirror Images

Students sometimes need help with the concept of plane of symmetry and mirror images. Proper bilateral symmetry displays a single, central plane of symmetry. However, as we have seen in Investigation 4, this does not mean the two halves are identical. They are different in that one side of the plane of symmetry is the mirror image of the other side.

Below is an illustration of the human skeleton and an ordinary housefly showing the placement of a mirror along the body’s midline. Because both the human and fly are bilaterally symmetric, the reflected mirror image accurately represents the complete animal.

Leonardo stressed the perfect bilateral symmetry of the human body in his famous drawing of the Vitruvian Man sketch below. This drawing was found among his many journals and depicts the beauty and art of science and, at the same time, the science in art

In this Performance Assessment, students will have an oppertunity to revisit the concepts of perspective and bilateral symmetry in art. In doing so, they will use skills they practiced throughout the Science and Art CELL.