Maurice Mikkers has been using microscopic imaging to study the salt crystallizations of single tears. At first, he says, he was curious to find whether different patterns would emerge as a result of the tears' particular origins. Would we be able to look at the microscopic patterns and discern whether the subject had been weeping from a broken heart, or merely slicing an onion? It turned out that the cause of the tear had little influence on the patterns that formed. Whatever tales the crystals may tell are inscrutable to the viewer.
Each teardrop creates its own world, and no amount of looking from our viewing distance will tell us more about the life within. That doesn't make them any less captivating.
The tools of scientific visualization have a history of coming up short when it comes to showing us what we want to see.
The image above was an early study of the moon by James Whipple, which we're seeing in the form of a salt print. The source of the cloudy penumbra hovering over the dark side is unclear. It seems likely that it's a visual artifact from within the telescope itself, but it doesn't have the familiar look of the kind of lens flares that grace today's sun-washed selfies. Whipple would go on to make daguerreotypes that rendered the moon's texture much more sharply. But it would be decades before the public would be delighted by the clarity of imaging in James Nasmyth's The Moon: Considered as a Planet, a World, and a Satellite.
These images were too clear to be true, photographically speaking -- the technology still didn't exist to capture this kind of astronomical detail in print. Nasmyth created his illustrations by photographing plaster molds he'd made, which were in turn based on photographs and other existing forms of documentation. These were meticulously crafted to match up to thorough maps of the moon's features, and these maps are also included in the book. Beyond the plaster models, Nasmyth put a variety of materials to use in effort to demonstrate theories about the physical forces that had formed the moon's surface.
Nasmyth saw his work as science, not fiction; all of these techniques were deployed for the purpose of demonstrating ideas that he had done his best to work out empirically. To the viewer, the images seem to stand squarely in the way of the line between illustration and evidence. As we use it today, photography serves a thousand purposes , but Nasmyth's readers had reason to expect photographs to be much more concrete in their rendering of fact. Photographs were trusted as scientific evidence for all kinds of ideas, from spiritualism to eugenics. The medium was making it possible to see the invisible in so many new ways; who could guess what kind of visual evidence would be the next to be discovered?
The nineteenth century camera was treated first and foremost as a mechanical apparatus that recorded reality faithfully. But there will always be limits to what the image can pin down. Then as now, when the image captivates the viewer, we can't help but see in it evidence of what's just beyond its grasp.