AI Helps ID Paint Chemistry of Berlin Wall Murals (arstechnica.com) 17
An anonymous reader quotes a report from Ars Technica: The fall of the Berlin Wall in November 1989 was a seminal moment in 20th century history, paving the way for German reunification. Many segments, both large and small, were preserved for posterity -- including portions covered in graffiti or murals. A team of Italian scientists used a combination of spectroscopic analysis and machine learning to study paint chips from wall fragments to learn more about the chemistry of the paints and pigments used, according to a new paper published in the Journal of the American Chemical Society. [...] Nondestructive techniques like Raman spectroscopy are often used to identify the molecular signatures of pigments, dyes, and other chemical compounds, but this usually requires bringing samples to the lab. Handheld Raman devices are used for cases where analysis must be done on-site, but they are far less precise than full-size laboratory equipment. So [Francesco Armetta of the University of Palermo and co-authors of the paper] decided to adopt a machine-learning approach to enhance the precision and sensitivity of spectral data collected by those handheld devices.
The team collected 15 pictorial fragments of five different colors from Berlin Wall paintings. They used handheld Raman spectroscopy on the paint chips and compared that spectral data to a commercial library of pigment spectra, confirming those findings with X-ray fluorescence and optical fiber reflectance spectroscopy. Most of the fragments had two top layers that had been painted with a brush rather than spray paint; brushstrokes were clearly visible under a microscope in several cases. The underlying third layer, in contact with the masonry, was white and probably used to prepare the surface for painting. Calcium and titanium were the most abundant elements in all the samples. Chromium and lead were present in a green-colored sample, and the authors think this was mixed with another color to get that particular shade. There were also traces of copper in blue and green samples.
Armetta et al. also created their own mock-up samples by mixing commercial German acrylic paints (commonly used since the 1800s) in different ratios to try to match colors and tints from the fragments -- crucial information for restoration. This is where their machine-learning algorithm (dubbed SAPNet) proved useful. They trained it on the Raman spectral data from the Berlin Wall samples and used it to determine the percentage of pigment. The model concluded that the Berlin Wall paint chips contained titanium white and as much as 75 percent pigment. "The identification of most of the components of the fragments was only possible through the comprehensive evaluation of the results provided by all the techniques [combined]," the authors concluded, further augmented by the development of SAPNet. "While SAPNet was specifically tailored for pigment mixture analysis, its robust framework demonstrates the transformative potential of deep learning methodologies for Raman spectral analysis across diverse scientific and industrial applications."
The team collected 15 pictorial fragments of five different colors from Berlin Wall paintings. They used handheld Raman spectroscopy on the paint chips and compared that spectral data to a commercial library of pigment spectra, confirming those findings with X-ray fluorescence and optical fiber reflectance spectroscopy. Most of the fragments had two top layers that had been painted with a brush rather than spray paint; brushstrokes were clearly visible under a microscope in several cases. The underlying third layer, in contact with the masonry, was white and probably used to prepare the surface for painting. Calcium and titanium were the most abundant elements in all the samples. Chromium and lead were present in a green-colored sample, and the authors think this was mixed with another color to get that particular shade. There were also traces of copper in blue and green samples.
Armetta et al. also created their own mock-up samples by mixing commercial German acrylic paints (commonly used since the 1800s) in different ratios to try to match colors and tints from the fragments -- crucial information for restoration. This is where their machine-learning algorithm (dubbed SAPNet) proved useful. They trained it on the Raman spectral data from the Berlin Wall samples and used it to determine the percentage of pigment. The model concluded that the Berlin Wall paint chips contained titanium white and as much as 75 percent pigment. "The identification of most of the components of the fragments was only possible through the comprehensive evaluation of the results provided by all the techniques [combined]," the authors concluded, further augmented by the development of SAPNet. "While SAPNet was specifically tailored for pigment mixture analysis, its robust framework demonstrates the transformative potential of deep learning methodologies for Raman spectral analysis across diverse scientific and industrial applications."
But...why? (Score:4, Insightful)
How is this of any significance to humanity? Seems like a weird way to waste both time and money.
Re: (Score:2)
It's called knowledge. This same, or similar, process could be used to determine the paint structure from Egyptian paintings, or Olmec paintings, or anywhere we don't know how the colors were created.
I realize knowledge and facts are going by the wayside, but it can't hurt to learn something new.
Re: (Score:3)
While there's a lot to be learned about paint used by ancient Egyptians, the paint on the Berlin wall is probably whatever was on the shelf at the nearest hardware store at the time. Not knocking the historical significance, but it's just paint.
Re: (Score:2)
For this, yes, it was probably whatever paint someone picked up. However, by identifying it without using destructive methods, this can then be done elsewhere such as what I previously mentioned.
This could be used in medical research, metalurgy, and other fields where destroying the object isn't feasible or possible. Think of glazing from a thousand years ago. What did they use? What were its components? There are a myriad of applications for this.
Re: But...why? (Score:3)
Should be categorized as non-algorithmic research (Score:2)
" The study reveals the ability of the convolutional neural network (CNN) algorithm to analyze the spectra and predict the ratio between the coloring compounds."
Reducing science research to input data, output data, and a match percentage via AI model should be categorized as less than top tier science research.
Nowhere in this does the research lead to an expressible function or set of equations giving an input and producing a confident output. It omits the expressible function and omits the set of equation
Re: (Score:2)
*any decade now.
Re: (Score:2)
Would you rather it have been wasted on more Quantum Computing*? *any decade now.
Be careful, the new laws have harsh punishments: Thou shalt not mock qubits!
Re: (Score:2)
This is actually a good use of AI/ML. As TFA mentions, this is about preservation and restoration of historically important artifacts. It's can also be applied to restore murals and historic adverts elsewhere that have been vandalized or have degraded over the decades. It can also help find paints that haven't degraded, which will lead to further advancements in paints and other coatings that will withstand weathering effects. So it's not just the arts and humanities that win. Even industry stands to gain f
Re: (Score:2)
Re: (Score:2)
Was my exact thought, someone probably used AI to come up with a thousand random proposals for grant funding and this is the one that made it through.
Re: (Score:2)
How is this of any significance to humanity?
They're improving the tech used to analyze the details of the paint used. Honestly the article wasn't very long.
Re: (Score:2)
Probably a demonstration for their process or abilities.
not enough problems in the world (Score:1)
so these guys decided to solve the mystery berlin wall paint
Re: (Score:2)
so these guys decided to solve the mystery berlin wall paint
Maybe next they'll tell us what kind of metal was used for the Eiffel tower!
Solving first world countries problems (Score:2)
because you would not like to find out that some IG Farben paint was used on the wall 50 years from now.