History excels, sometimes, in poetic justice. What digital photography does today for analog film, the first cameras did for portrait painters more than a hundred and fifty years ago. * On the milestones of photography technology
The 'interesting times' here are in the sense of troubled, or turbulent times. To be honest no one really knows if this proverb is really Chinese in origin, or if it has been attributed to the Chinese throughout history simply because any proverb that has an ancient Chinese origin must be a wise proverb. Another ancient Chinese proverb says, if you don't have anything smart to say, say an ancient Chinese proverb.
In any case, the reason I started the chapter with the proverb about the interesting times is because, at least technologically, we live in a really fascinating time. Contrary to the original intention of the curse, these times are actually interesting from a positive point of view: the technological changes that have taken place in the last decades are truly amazing. The invention of the Internet is an example of such a revolution, as well as cellular communication, which is spreading around the world like water breaking out of a collapsing dam.
One of the revolutions we are going through in recent years is the transition from analog photography to digital photography. This transition, from thirty or so images on film that is rolled up in a small roll to compressing hundreds and thousands of images in a memory card the size of which does not exceed an average fingernail, is happening right before our eyes in recent years. The pace at which this whole thing is happening is truly breathtaking - in less than ten years we have gone from a situation where a digital camera is rare, expensive, cumbersome and inferior in terms of quality, to the opposite situation. Try to buy a new analog film camera today. The shop assistant will look at you as if you fell from the sky.
But history excels, sometimes, with poetic justice. What digital photography does today for analog film, the first cameras did for portrait painters more than a hundred and fifty years ago. We'll get to that right away, but first a few words about the scientific developments that preceded the invention of photography.
The origin of the word Camera, a camera in English, is from the Latin word 'room'. Room, camera - what's the connection? So there is a connection, even a close connection. Back in the days of Aristotle, and perhaps even earlier, scholars were aware of an interesting optical phenomenon. If you take a box and make a small, really tiny hole in one of its sides - the image you will see on the inner side of the box, the one opposite the hole, will not be just a blurred spot of light - but a projection of the outside world, like a movie projected on a screen in the cinema. This phenomenon only occurs if the hole is really small, if the hole is too big, the image on the wall will be blurry and unclear.
This optical trick greatly intrigued early scientists. Researchers such as Leonardo da Vinci and the Egyptian Ibn al-Haytham a few hundred years before him, conducted studies and measurements and tried to explain it. Since it is a bit inconvenient to crawl into a small box to see the image that is formed on the inner wall, they would build a full-sized room and make a small hole in the wall. The room was dark, of course, so that the projection on the wall could be seen and the name 'camera obscura' - in Latin, 'dark room' - is the name given to these dark rooms.
How is the image created on the wall inside the camera obscura? The answer is quite simple, and was clear even to the scholars of that time. The light rays move in straight lines - like a flashlight beam, for example. The rays pass through the hole and hit the wall inside the room. If the hole is very large, like a window, then to every point in the wall come masses of rays from many different directions, and then all that is seen will be a casual spot of light. But if the hole is small enough, then only one ray of light will reach each point in the wall: a single flashlight beam, if you will. In the created state, each point on the wall reflects a ray of light coming from a single source in the outside world: in fact, we received the arrival of the outside world, on the wall inside the camera obscura.
The basic camera obscura were not perfect: the image projected on the wall was very weak and not always perfectly focused. The main use of them was for astronomical observations of partial solar eclipses - they would project the partial eclipse onto the wall while the moon was covering the sun, so you could observe the eclipse without taking the risk of the strong light from the sun frying your eyes.
The camera obscura also attracted the attention of the painters, who quickly realized that the shadow projected on the wall could be used as an excellent aid for painting: with the help of the camera obscura, the landscape reflected through the hole can be sketched in general lines on the page, resulting in a more real and accurate perspective in the painting. The camera obscura was particularly useful for this purpose when technological developments in the field of lens polishing made it possible to insert a focusing lens into the small hole, so that the image on the wall was brighter, sharper and clearer. The use of lenses also makes it possible to reduce the size of the camera obscura, from a large room to a box that can be easily moved from place to place.
Although the camera obscura was an excellent tool for painters, not many rushed to adopt it for their own use. Some artists thought that a real painter should not use such 'tricks': a real painter paints by eye, just as real drivers do not drive a car with an automatic transmission. Others felt that there was something 'unnatural' in the apparition projected on the wall, as if the devil was trying to tease them, what's more, the image projected on the wall inside the camera obscura would be received when it was reversed, this is due to the optical properties of this phenomenon. Devil or no devil, the camera obscura eventually became more and more common among artists, and today this pair of words is mainly associated with the field of art and, as we immediately see, with photography.
Another science whose development was critical to the development of photography was chemistry, and especially the study of how certain substances react to light. Since the sixteenth century, and perhaps even earlier, scientists have known that certain compounds exhibit intriguing behavior when exposed to light. Various combinations of the elements silver and chlorine, or silver and nitrogen, turn black in the presence of the sun's rays. The biggest setback for photography was that these processes were reversible, and any image imprinted on such a chemical compound would not survive long before fading and disappearing.
Can horses fly, or: on the history of photography - Part II
מקור
This article is taken from the show's script.Making history!', a bi-weekly podcast about the history of science and technology.
2 תגובות
I don't know the details of the history, but it seems very logical to me that the first attempt with a camera obscura really took place in a dark room and not inside a box and that the possibility of repeating it with a small box was discovered later.
As the author pointed out, people do not usually walk around inside dark boxes with a hole in the wall and even find it difficult to do so even when they want to. Dark rooms, on the other hand, most likely were.
I also know this from personal experience. I was not alive when the phenomenon was first discovered, but I encountered it many years ago by accident.
I noticed that in the mornings, when I woke up and opened my eyes, I would often see a very strange pattern of light on the ceiling of the room. One of the features in this pattern were two concentric circles with two black dots near the ends of one of the diameters of the inner circle.
When I tried to think what was causing this, I quickly came to the conclusion that I was in a camera obscura (it must be understood that I already knew the concept even before the experiment) and that the two circles were nothing but the opening of the sewer on the balcony next to the window of the year room. It turns out that between the slits of the shutter that closed the window of the year's room there was a small defect that functioned as a hole and allowed the projection of the image of the balcony onto the ceiling.