Divina proportio - proportion has been known since antiquity. This is a way of dividing the composition in the ratio of 1 to 1.618, which reflects the most aesthetically pleasing feelings for our eyes. So far, no one has proven why this is actually the case. The golden mean occurs in the environment of plants and animals, in the structure of man, his nervous and circulatory systems, it is associated with the cycle of brain waves and even quantum physics. Euclid explained the term as follows: "A straight line is divided in a golden manner when the ratio of the whole line to the greater segment is equal to the ratio of the greater to the less." This knowledge is very useful in product photography.