The 2017 Jackie Chan movie “Kung Fu Yoga” features professor Jack Chan, most famous archaeologist of China, on his quest to find the treasure of Magadha. During his adventure, he uses a couple of interesting (fictional) technologies, which we will take a closer look on…
Kung Fu Yoga (2017, Sparkle Roll Media) is a movie about Chinese Archeology professor Jack (Jackie Chan), who wants to locate the lost treasure of Magadha. After some adventures and spectacular fights, he and his team eventually find a mountain temple in India, where the treasure is hidden. There are also a couple of references to Indiana Jones: Raiders of the Lost Ark (1981): At the beginning of the movie, a girl has painted hearts on her eye lids to show her affection to one of the assistants or at the end of the movie, the treasure is found by putting a sceptre onto a certain spot to let light shine through to reveal a hidden switch. Jack even tells us, that “he likes Indiana Jones” to make the references perfect. Throughout his journey, Jack uses technology to do his archaeology. Some of it is pretty usual like drones, but one technology is in parts fictional, although represents archaeoinformatics at its finest.
At the beginning of the movie (6:20-7:10), he shows some of his students a new technology to reveal the colour pigments of ancient terracotta statues. First, he sprays a reagent onto the statue and afterwards scans the statue with a hand-scanner. Wirelessly, the data is transferred to his laptop, where the true and lost to the visible eye colour appears within seconds.
Before we begin though, as you might not know, the terracotta statues were indeed all painted. The colours were used during the Qin Dynasty (221-206 BCE) and the terracotta army of Emperor Qin Shi Huang (259-210 BCE) were painted in different colours. While excavating, the colours are still visible, but vanish after only four minutes, when they are in contact with air. The colours of blue and violet are made of a synthetic barium copper silicate. Other colours include scarlet, pink, green, jujube red, azure, pink-purple and reddish brown. To preserve the colours, researchers use a complicated method of cleaning and wrapping up the statues. Only this way, the colours can be preserved, but only for about ten years.
The first thing about the technology used in the movie is, that reagent Jack sprays onto the statues. According to him, there is no harm done to the statues, but I have to ask, what is it really doing then? If the reagent is necessary to transform an unscanable colour trace into something that the scanner can pick up, I am guessing that the reagent will alter the chemical structure of the colour pigments remaining on the terracotta figure. It might be possible, that the reagent is a chemical cleaning solution to get rid of unwanted residue to enable the scan, but cleaning is a more complicated process than simply spraying a reagent onto a surface.
Another open question remains on how the 3D scan of the statue was made during the scanning process, as the result on the laptop suggests, that the color information is already placed on top of a 3D scan of the statue. 3D hand-scanners are available and although they can achieve very good results, the result we see in the film sequence could not have been possible with the way Jack was working the scanning device. The last, but most important question remains: how can a scan detect the colours on the terracotta statue?
The technology used, is most probably the so-called “portable X-ray flourescence” (or short: pXRF). pXRF is a nondestructive way of measuring chemical elements on surfaces. So basically, it is possible to scan non-visible colours, but in reality the scanning device needs to be much closer, nearly touching the surface. Also, the calculation of the scanned results is a more complicated process than presented in the movie sequence. First the scanner emits x-rays onto the object, which loosen electrons from the atoms of the scanned material. As the atoms adjust for the missing electrons, the energy emitted for doing that is detectable by the scanner. For this to work, the scanned elements need to have a minimum of electrons in their configuration. Therefore, not all elements can be scanned.
So basically it is possible to scan the elements on a surface, but what does seem a bit far fetched is the application of the scanned results onto a perfect 3D model just waiting to be coloured and the distance the scanner is held by the archaeologist. Nevertheless, nothing speaks against developing this technology further in order to become as convenient as it is shown in the movie “Kung Fu Yoga” by Jackie Chan.