Technology



The Evolution of the Camera



A Short History Of Photography (Adapted from Wikipeida)

In almost 200 years, the camera developed from a plain box that took blurry photos to the high-tech mini computers found in today's DSLRs and smartphones.

The First Permanent Images

Photography, as we know it today, began in the late 1830s in France. Joseph Nicéphore Niépce used a portable camera obscura to expose a pewter plate coated with bitumen to light. This is the first recorded image that did not fade quickly.
Niépce's success led to a number of other experiments and photography progressed very rapidly. Daguerreotypes, emulsion plates, and wet plates were developed almost simultaneously in the mid- to late-1800s.

Niépce's experiment led to a collaboration with Louis Daguerre. The result was the creation of the daguerreotype, a forerunner of modern film. A copper plate was coated with silver and exposed to iodine vapor before it was exposed to light.
To create the image on the plate, the early daguerreotypes had to be exposed to light for up to 15 minutes.

The daguerreotype was very popular until it was replaced in the late 1850s by emulsion plates.

Emulsion Plates

Emulsion plates, or wet plates, were less expensive than daguerreotypes and required only two or three seconds of exposure time. This made them much more suited to portrait photographs, which was the most common use of photography at the time. Many photographs from the Civil War were produced on wet plates.

These wet plates used an emulsion process called the Collodion process, rather than a simple coating on the image plate. It was during this time that bellows were added to cameras to help with focusing.

Two common types of emulsion plates were the ambrotype and the tintype. Ambrotypes used a glass plate instead of the copper plate of the daguerreotypes. Tintypes used a tin plate. While these plates were much more sensitive to light, they had to be developed quickly. Photographers needed to have chemistry on hand and many traveled in wagons that doubled as a darkroom.

Dry Plates

In the 1870s, photography took another huge leap forward. Richard Maddox improved on a previous invention to make dry gelatine plates that were nearly equal to wet plates in speed and quality.

These dry plates could be stored rather than made as needed. This allowed photographers much more freedom in taking photographs. The process also allowed for smaller cameras that could be hand-held. As exposure times decreased, the first camera with a mechanical shutter was developed.

Cameras for Everyone

Photography was only for professionals and the very rich until George Eastman started a company called Kodak in the 1880s.

Eastman created a flexible roll film that did not require constantly changing the solid plates. This allowed him to develop a self-contained box camera that held 100 film exposures. The camera had a small single lens with no focusing adjustment.
The consumer would take pictures and send the camera back to the factory for the film to be developed and prints made, much like modern disposable cameras. This was the first camera inexpensive enough for the average person to afford.

The film was still large. It was not until the late 1940s that 35mm film became cheap enough for the majority of consumers to use.


Photographic Equipment in the 1850’s

Humphrey Lloyd Hime brought his full kit with him to document the Hind Expedition. His camera had a two inch portrait and a two inch landscape lens. The rest of his supplies, including chemicals, containers, etc., conformed to the requirements listed in Hardwich's Manual of Photographic Chemistry, a copy of which he carried with him. This served as a basic guide offering complete instructions on the practice of wet plate photography.

Collodion wet-plate photography was the process of both the portrait and landscape photographer of the 1850s. For landscape photography it produced some spectacular results, but required a lot of bulky and cumbersome equipment and supplies. The portable darkroom had to be right there, because the whole process had to be done while the collodion was still wet. The most common portable darkroom was some sort of collapsible tent and pole structure that could be assembled or dismantled in a few moments and carried on a man's back with little inconvenience.

To use the darkroom the photographer put the top part of his body through the opening and had the cord tied tightly around his waist while his arms and upper part of his body remained free to move about within the tent.

Glass plates were used in a variety of sizes depending upon the specifications of the camera and the lens systems employed. For field work the supply of glass plates was normally carried in a grooved wooden box. This box would be placed carefully close at hand near the darkroom tent.

The camera with its lens would be set up on a sturdy wooden tripod. 
When the plate was well cleaned and polished it was coated with the photographic collodion emulsion which was the vehicle for retaining the sensitive silver salts.
The coated plate was now ready for sensitizing in the Nitrate Bath - a combination of Silver Nitrate and cold water. The Nitrate Bath could also be prepared in advance and stored in a bottle. However, the Bath was sometimes a problem for the landscape photographer as it decomposed when agitated in transit.

To sensitize the plate the field photographer had to use his darkroom tent. It took great care as the solution was corrosive and caused bad staining. The plate was sensitized in the Bath for varied lengths of time depending upon the weather - in hot temperatures thirty to forty seconds - in cold one to five minutes. The sensitized plate was removed from the Bath, allowed to drain and placed in a clean, dry dark slide ready for carrying to the camera.

The photographer gently rested the dark slide with its sensitized wet-plate on the ground in a shaded area. He then made the final adjustments to his camera and lens. Removing the lens cap and throwing the focusing cloth over himself and the back of the camera, the photographer peered through the ground glass and adjusted his focus, aperture and camera angle. Satisfied that all was in order he inserted the dark slide with its plate in the camera. He then made the exposure.

Exposures for wet-plates were relatively long. For example:

thirty seconds for a distant view with sky and water
three minutes for a near view well lighted
six to ten minutes for interior views
six to ten minutes for forest scenery with light from above.

Development as soon as possible after sensitizing and exposure was preferable.
It was an exacting operation. The exposed plate was removed from the dark slide. The Pyro-Gallic solution was poured evenly on the plate held in the hand. Moving the plate to keep the solution moving, the photographer closely watched the development for thirty to forty seconds until the image appeared sufficiently
intense. Knowing the exact development time was mainly a matter of experience.

The plate could now be brought out of the darkroom tent for further processing. 
Fixing the negative plate to render the image indestructible by light was the next operation. The photographer poured t as substance called Hypo on and off the plate until all the excess iodide was cleared away. The Hypo was then washed away. This final washing was best done over a three to four hour period, changing the water several times. Once assured that all the Hypo was removed the plate was then placed in the sun or some heated area to dry.

It was an exacting operation requiring definite skill and artistry, a goodly amount of physical stamina and energy, sufficient time, and not a little good fortune in terms of weather, climate and environment.

https://www.thesprucecrafts.com/brief-history-of-photography-2688527
https://www.cameraheritagemuseum.com/cameras

 

Local museums  feature displays tracing the evolution of cameras.
    


An example of a glass-plate negative from the Elgin Museum