Quem Inventou a Fotografia? Como a Imagem é Capturada?

The Origins of Photography

The Concept of Photography

• Photography is perceived differently by individuals; for some, it serves as a nostalgic window to the past, while for others, it is a means of financial survival.

• The inception of photography is rooted in two key principles: image projection through a dark chamber and the discovery of light-sensitive substances.

Historical Background

• References to the camera obscura date back to ancient texts from China (400 BC) and Aristotle's writings (330 BC), indicating its long-standing significance.

• Persian scholar Alhazém (circa 1000 AD) utilized the camera obscura to demonstrate that light travels in straight lines, explaining why images appear inverted.

Advancements in Optical Devices

• By the 1600s, high-quality lenses were invented, allowing artists and engineers to use the camera obscura for more precise drawings without losing image clarity.

• The invention of magic lanterns emerged from these optical principles, projecting images onto walls using glass slides—an early form of entertainment.

Early Experiments with Light Sensitivity

• Prior to permanent image capture, drawings were the only method for recording visuals. Johann Heinrich Schulze began experimenting with light-sensitive chemicals around 1724.

• Schulze discovered that silver nitrate darkened when exposed to light but did not create permanent images due to continued exposure effects.

The First Photograph

• Joseph Nicephore Niepce captured the first photograph in 1826 using a dark chamber. His lack of drawing skills motivated him to find a way to fix images permanently.

• After numerous experiments starting in 1816 with silver chloride paper, he finally succeeded using a tin plate coated with bitumen dissolved in lavender oil.

Process Development and Collaboration

• Bitumen hardened upon light exposure allowed Niepce’s process to differentiate between light and dark areas after an eight-hour exposure time.

• Despite its primitive quality compared to modern photographs, Niepce's work marked a significant milestone in visual documentation.

Daguerre's Contribution

• Louis Daguerre partnered with Niepce in 1829 but faced challenges after Niepce's death in 1833. Their collaboration led to advancements in photographic processes.

• In 1839, Daguerre introduced the daguerreotype process which reduced exposure times significantly and enabled clearer portraits through innovative techniques involving polished copper plates.

The Evolution of Early Photography Techniques

The Daguerreotype Process

• The initial step involved using a black cloth to enhance visibility, followed by exposing the plate in a dark camera for 10 to 30 minutes depending on light conditions.

• After exposure, the plate was revealed using heated mercury vapor, which made the previously invisible image visible but posed health risks to photographers.

• An example from 1838 shows a busy Paris street captured with impressive quality; however, due to over 10 minutes of exposure, moving objects did not appear in the photo.

• The resulting images could be both positive and negative based on lighting and viewing angles; lighter areas appeared white while shadows displayed various shades of gray.

• A later photograph taken between 1846 and 1852 showcased detailed lunar features after multiple exposures, contributing to Daguerre's international fame.

Popularity and Limitations of Daguerreotypes

• By August 1839, Daguerre received a pension from the French government in exchange for presenting his invention as France's gift to the world; this led to over 70 photography studios in New York by 1850.

• Despite its popularity, daguerreotypes had drawbacks such as toxic mercury use and the inability to replicate images—each photo was unique.

Talbot's Innovations

• William Henry Fox Talbot worked concurrently on photographic processes and only learned about Daguerre’s work in 1839 when it became publicized.

• Talbot experimented with silver salts starting in 1834 aiming to fix images onto paper, leading him towards what would become known as "salted paper" process.

Development of Negative Processes

• His method involved coating paper with sodium chloride solution before applying silver nitrate, creating a light-sensitive surface that produced negatives through prolonged exposure.

• Talbot’s innovation allowed for multiple copies from one negative by placing it over another piece of photo paper exposed to sunlight.

Advancements in Photography Technology

• In parallel developments around 1840, Max Petzval improved lens technology significantly enhancing light capture compared to earlier lenses used by Daguerre.

• Petzval's lens increased light intake by approximately 22 times which reduced exposure time dramatically but still faced competition from Talbot’s slower processes.

• In response to challenges with image quality and speed, Talbot refined his technique in 1841 replacing chemicals for better sensitivity leading to faster exposures termed "Calotype."

Transitioning Towards Practical Solutions

• Despite improvements under Calotype methods being marketed as superior, many found them inferior due to graininess caused during positive transfers from negatives.

• A significant shift occurred around 1879 with dry gelatine plates allowing photographers greater convenience without needing hazardous chemicals or immediate development post-capture.

History of Photography and Innovations

Early Developments in Photography

• The introduction of silver nitrate in emulsion allowed for more stable and detailed negatives, requiring only a few seconds of exposure.

• Photographers could now use dry plates, enabling them to take photos and develop them later with the help of technicians, making photography more accessible.

• The process using silver gelatin was not limited to dry plates; it also became prevalent in photographic paper and films, dominating black-and-white photography in the 20th century.

George Eastman's Revolution

• In 1888, George Eastman registered the Kodak brand, introducing roll film and the Kodak camera that democratized photography for the masses.

• The flexible roll film developed by Eastman replaced fragile glass plates, allowing multiple negatives to be stored conveniently.

• This innovation enabled photographers to easily enlarge negatives into larger prints while maintaining image quality.

The Kodak Camera's Impact

• Eastman's patented camera was designed to promote roll film sales with a simple motto: "You press the button, we do the rest."

• For $25 at that time, amateurs could buy a camera capable of taking 100 photos; after finishing the film, they would send it back for processing and printing.

• By 1900, Kodak launched the Brownie camera aimed at children and young people for just $1. Its popularity led to high demand.

Origins of Photography Terminology

• The term "photography" was coined by Brazilian inventor Antoine Hercules Romuald Florence in 1833 from Greek words meaning "drawing with light."

• Florence's early attempts at capturing images occurred around 1832 using silver chloride sensitized paper before other notable inventors like Daguerre.