I was intrigued to read how Stone Age art - paintings on the walls of caves - took on an entirely new perspective when viewed using the sources of light that would have been available to the artists, rather than modern lighting.
In the wide chambers and narrow passageways of Isuntza I Cave in the Basque region of Spain, the researchers tested torches, stone lamps and fireplaces — nooks in cave walls. Juniper branches, animal fat and other materials that Stone Age humans would have had at hand fueled the light sources. The team measured flame intensity and duration, as well as how far away from the source light illuminated the walls.
Each light source comes with its own quirks that make it well suited to specific cave spaces and tasks ... Torches work best on the move, as their flames need motion to stay lit and produce a lot of smoke. Though torches cast a wide glow, they burn for an average of just 41 minutes, the team found. That suggests several torches would have been needed to travel through caves. Concave stone lamps filled with animal fat, on the other hand, are smokeless and can offer more than an hour of focused, candlelike light. That would have made it easy to stay in one spot for a while. And while fireplaces produce a lot of light, they can also produce a lot of smoke. That type of light source is best suited for large spaces that get plenty of airflow, the researchers say.
For Intxaurbe, the experiments confirmed what he has seen himself at Atxurra cave in northern Spain. In a narrow Atxurra passageway, Paleolithic people had used stone lamps. But near high ceilings where smoke can rise, they left signs of fireplaces and torches. “They were very intelligent. They use the better choice for different scenarios,” he says.
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A lack of the right lighting also played a part, Intxaurbe and colleagues say. By simulating how torches, lamps and fireplaces lit up a virtual 3-D model of Atxurra, the team saw the cave’s art with fresh eyes. Using just a torch or a lamp from below, the paintings and engravings stay hidden. But lit fireplaces on the ledge illuminate the whole gallery so that anyone on the cave floor can see it. That suggests the artists may have wanted to keep their work hidden, the researchers say.
Cave art wouldn’t exist without harnessing fire. So to unravel the mysteries of subterranean studios, it’s key to understand how prehistoric artists lit their surroundings. “Answering the small questions in an accurate way,” Intxaurbe says, is a path toward answering a main question about Stone Age people, “why they painted these things.”
There's more at the link.
When you think about it, that's a very interesting insight. We're used to works of art created in well-lit studios, painted in natural light or artificial light that approximates natural light. Our Stone Age ancestors didn't have that luxury. They had to not only translate what they'd seen outside their caves, in the light of day, into symbols and images that would be meaningful in the low, fitful light of the sources available to them; they also had to ensure that their communities could understand and appreciate their efforts to portray the world outside the caves. In a culture that existed before languages developed, where expressing abstract concepts was probably unheard of, what were they trying to convey through their art, and how were they trying to convey it?