Mona Lisa in 3D
If placed side by side, the Mona Lisa of Louvre and Mona Lisa del Prado form a stereogram image. A stereogram image is an image pair, which can be studied using the cross-eye-technique: the right eye is focused on the left image and the left eye on the right. This way, the two images will cover each other and merge. If the images are meant to do this, the result will be seen in 3D. It might be helpful to maintain enough distance to the image-pair and perhaps to use the palms of your hands covering your eyes from the sides.
The cross-eye technique was already used in ancient Egypt in Sun-gazing meditation. It has since been used successfully e.g. by sculptors in creating two exactly identical statues - who knows, perhaps Leonardo also used this technique in painting the two identical Mona Lisas. In 2013 a paper was published on the 3D qualities in Mona Lisa: see Da Vinci’s Mona Lisa entering the next dimension. (Carbon & Hesslinger, 2013)
Image 23. The Mona Lisas as a stereogram image
Image 24. Virgin on the Rocks –stereogram
Another 3D-painting of Leonardo da Vinci is the Virgin of the Rocks. Using the cross-eye technique, the pair produces certain highlighted forms in the background landscape. Also, the finger pointing to the reed cross is highlighted. It should be noted that the Virgin on the rocks supports the observations made with the Mona Lisa: in both paintings Leonardo refers to certain units of measurement such as the reed. Furthermore, the reed cross is also familiar to us from Leonardo’s painting St John the Baptist, which is also at the Louvre Museum. John the Baptist will play remarkable role in the end of this study.