Before Photography - Photographic Processes Series - Chapter 1 of 12
About this video
Photography grew out of many experiments rather than one discovery. Before it, people traced shadows to make silhouettes and used devices such as the pantograph and physionotrace to shrink them, and the camera obscura projected images into a dark room. Schulze proved that light, not heat, darkened silver compounds, and Wedgwood made images on silver-nitrate paper and leather but could not fix them.
You'll be able to
- explain how silhouettes, the pantograph and the physionotrace made more objective portraits.
- describe how a camera obscura produces an image.
- explain what Schulze proved and what problem Wedgwood could not solve.
Key words
- photography
- From Greek words meaning 'light drawing'.
- silhouette
- A traced outline of a shadow, often of a person's profile.
- pantograph
- A device of linked bars that copies a traced drawing at a smaller size.
- physionotrace
- Chretien's device that traced a person's shadow through levers and reduced it at the same time.
- camera obscura
- Latin for 'dark room': a darkened room or box where light through a small hole projects an image of the outside.
- photogram
- An image made by placing an object directly on light-sensitive material and exposing it to light.
Transcript
The invention of photography was not one discovery that led to what we understand as photography today. There are winners and losers in the evolution of photography. It’s so fascinating at every different point in its history The way that we familiarize ourselves with the world around us just fundamentally changed with photography.
The silhouette is really the essence. That’s the essence of a person’s soul and people knew that. The term photography in Greek is light drawing. So when you’re drawing with light, you can do it with chemicals but before photography you would look at the shadow you would trace the shadow.
The problem with drawing a shadow with someone is that if you put a person in a room and you put a candle on one side of that person and it casts a shadow it’s a very big shadow. So the biggest problem is how do you take a very big shadow and make it into a little tiny shadow.
So there are tools that they used. The Pantograph machine that has these intersecting bars with a pencil and you could trace the large object and it would make it into a very small object. There was an inventor by the name of Chretien, who invented a device that would trace the shadow of a person through a series of levers.
It would then reduce the picture at the same time. And this instrument is called a Physionotrace. The thing about the silhouette and the Physionotrace that made them different from a painted portrait was that they were mechanical. They were much more objective portraits of individuals.
Unlike paintings, which were very subjective. Camera Obscura means dark room. That’s all it is. It’s a room with no light in it. And if you have a room with no light and you poke a little hole in the side of that room and you let light in from the outside, by miracle you’ll have an image projected upside down turned around, but in color and moving on the other side of the wall.
It’s a phenomena that people have been aware of for thousands and thousands of years. It’s easy to do. It’s very often the first project that is taught in photography classes just as a way to get people to understand the simplicity of what the camera is. Later improvements of the camera obscura included putting a lens in the hole so that the light could be focused so that you would have have a brighter and more focused image that would be projected on the wall.
But for photography the camera is essentially a box. The early experimenters of photography all knew that they wanted to make images in that box. The story of the invention of photography builds on experiment after experiment. Johann Heinrich Schulze is a German professor.
And in the case of Schulze’s experiment what you have is a glass jar and it’s filled with chalk. There’s some nitric acid and there’s some silver. It’s sparingly sensitive to light. So you have this jar with a barrier around the outside and when the light goes through the stencil it then darkens the chalk that is facing the glass on the inside of the jar.
And this is where Schulze contributes to the evolution of photography is that he’s proving that this is done by light, and not by heat. Thomas Wedgwood was the son of the famous potter, Josiah Wedgwood. The signature of the Wedgwood line was the decoration that was made of silhouettes.
It’s no surprise that one of the Wedgwoods would think that the light that makes a silhouette could also make an image by the action of light. Wedgwood is experimenting with silver nitrate. And he’s brushing silver nitrate onto sheets of paper and onto pieces of stretched white leather.
He was making images by doing contact printing of photograms. He was putting an object on top of the sensitive paper or leather. and when you put these in the sun it’s very easy to see the effect of light. You can see the paper darkening. So it makes sense he would want to make pictures in a camera obscura.
After all, camera obscuras have been used for years to make an image on a ground glass so you could do drawings. So you could see the effect of light coming into a camera obscura and producing an image. And yet he had no real success with his process. He wasn’t able to make those images last.
He wasn’t able to fix the image. Those images were fleeting. They disappeared after a certain amount of time. Talbot, Daguerre, Niepce all know about the work of Wedgwood because Humphry Davy, his friend had written an account of his work that was published in 1802.
It was a springboard from which other people could then do their own experiments.
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