The Science Of Capturing The Last Thing A Dead Person Saw Like A Photograph: Optography
Optography was once pursued as a way to capture the final image seen before death from the retina. Here is the strange history of the experiments, the science behind them, and why the idea ultimately failed.
Imagine thinking that the final image seen by a murder victim remained inside their eyes at the moment of death. Even more, imagine that this image could be extracted clearly enough to reveal the identity of the killer. It sounds like something between horror and science fiction, but for a time, some scientists took this idea seriously. That idea was called optography.
The word optography roughly means recording vision or writing an image. What scientists meant by this concept was simple: the final image formed on the retina could somehow be fixed after death and then transferred outward. This image was called an optogram.
Today it sounds bizarre, but in its own time the idea was not considered entirely ridiculous. Especially after the rise of photography, the comparison between the human eye and the camera became stronger. The retina was imagined as a kind of camera plate, and it was assumed that the image falling into the eye might leave a trace there.
Was The Eye Acting Like A Camera?
An important reason this idea gained strength was the discovery made in 1876 by the German physiologist Franz Christian Boll. Boll identified rhodopsin, a light sensitive protein found in the rod cells of the retina. When exposed to light, this protein would bleach. This led some researchers to believe that the eye might truly leave behind a chemical trace of an image.
Franz Christian Boll
Boll’s work was highly significant, but because his life ended early, he did not live to see where these studies might lead. The man who pushed the theory further was another German physiologist, Wilhelm Kühne.
Wilhelm Kühne
They Tried To Extract The Last Image From Rabbits’ Eyes
Kühne did not leave optography as a theory alone. He began performing experiments. He used many animals and, immediately after death, removed their eyes and tried to preserve the image on the retina. He tested different chemicals for this fixation process and eventually believed that the most suitable substance was potassium alum, or simply alum.
In one of his most famous experiments, he positioned a rabbit so that its head faced a barred window. From that position, the rabbit could see only the window and the cloudy sky. First, Kühne covered its eyes with a cloth for several minutes to let them adapt to darkness. The goal was to allow rhodopsin to build up in the rod cells. He then exposed the rabbit to light for three minutes. After that, the animal was decapitated, the eyes were removed, and the retina was carefully separated and placed into an alum solution.
The next day, Kühne believed he had obtained an image in which the window could be vaguely recognized on the retina. He called this image an optogram. In the published illustrations of the experiment, patterns resembling the bars of the window really could be noticed. This created great excitement at the time. Because if the method worked, then in theory the last thing a person saw at the moment of death could also be extracted from the retina.
The Human Experiment
This was Kühne’s real curiosity. After animals, he wanted to test the method on a human being. For this, the eyes of Erhard Gustav Reif, a prisoner executed in 1880, were removed after the execution and taken to the laboratory at Heidelberg University.
Kühne tried to produce optograms from those eyes as well. The resulting images have not survived, but some drawings and sketches connected to them appeared in publications of the time. It was even suggested that these sketches bore a superficial resemblance to a guillotine blade. Of course, there was one major problem here: people are extremely prone to seeing what they want to see. An ambiguous shape can very easily turn into an object loaded with meaning.
Could It Solve Murders?
This was the real attraction of optography. If the last image could be taken from a victim’s eye, then perhaps that image could show the face of the killer. In that sense, the eye could become a kind of biological camera and a witness to the crime scene.
Because of this idea, the subject also drew attention in forensic circles. Later, Dr. Maxime Vernois conducted a study to examine whether optograms could be used as evidence in murder cases. He also performed experiments on many animals. But his conclusion was extremely clear: it was impossible to find the portrait of a killer or a reliable representation of any object seen at the moment of death on a victim’s retina.
So optography looked fascinating on paper, but in practice it did not work. The shapes obtained were ambiguous, not repeatable, and far too open to interpretation. That made the method unreliable both scientifically and legally.
It Was Tried Again In 1975
The idea was not forgotten completely. In 1975, Heidelberg police wanted to reexamine Kühne’s findings using modern techniques. For this, they turned to the expertise of Evangelos Alexandridis at Heidelberg University.
Like Kühne, Alexandridis worked with rabbit eyes and succeeded in producing several high contrast images. In other words, it was shown again that certain light patterns could indeed form on the retina. But the conclusion was the same: optography had no value as a forensic tool. The resulting images could neither identify a killer nor provide the level of reliability required for courtroom evidence.
One Of The Darkest But Failed Detours In The History Of Science
Today, optography is not accepted as a valid scientific method. No one believes that a killer can be found by extracting the final image from a murder victim’s eye. But the idea still occupies a strange place in the history of science. Because for a time, people truly believed that the eye might preserve the last thing it saw, and they carried out serious experiments in an attempt to prove it.
Looking back now, optography feels like a mixture of naivety, dread, and obsessive curiosity. Still, it remains an extraordinary example of how the human mind moves between darkness and knowledge. On one side there is the desire for scientific progress. On the other, the urge to turn even the moment of death into data.
In the end, optography did not solve murders. It did not catch killers. It did not save courtrooms. But it remained in memory as one of the most unsettling and unusual ideas in the history of science. Because for a time, humanity genuinely wanted to believe one thing: death could seal the last image inside the eye.