With gelatin silver materials you start to get
manufactured photographic paper, manufactured film.
Once it became cheap and ubiquitous
it changed our relationship to photography fundamentally.
Everybody not only had been the subject of a photograph
but had made photographs themselves.
In the middle of the 19th century
nearly all processes that involved the use of silver nitrate
were made in a two step process.
Having a one step process would be infinitely easier.
And so, unlike say the wet collodion process where you
pour the collodion onto the plate and it has a bromide
and then you take that plate and dip it into silver nitrate.
Emulsion photography puts the bromide and the silver
into the same solution.
It was a combination of experiments done by several different people
but for the most part it’s an English invention.
Gelatin emulsions are made by taking gelatin
like the Jello you buy in the store today
and you put the gelatin into a container of water.
The gelatin is allowed to swell.
The swollen gelatin is melted.
you then pour in the bromide
pour in the silver nitrate and stir the solution.
So now you have silver bromide in hot gelatin.
This is an emulsion.
Now in the early 1880’s most of the gelatin dry plates
the glass plates were coated by pouring
the hot gelatin onto a hot glass plate.
Very much in a way that a collodion plate would be coated by hand.
Once you have a dry plate
now you don’t have to take a dark room into the field.
You don’t have to develop the plate before it dries.
You can take a package of plates, and you can go on a trip
expose the plates
and then weeks later come back to the comfort of your own dark room
and develop the plate and that’s an important discovery.
The same emulsion was applied to paper.
These are examples of gelatin silver prints.
The gelatin silver print was first introduced in the late 1800’s
The gelatin silver print is a developing out process
rather than a printing out process.
Printing out is when light strikes an object
and you actually see it visibly change.
Developing out, on the other hand, is a latent image
and what that means is that you just need a little bit of light
exposing this material
but you don’t see a visible change
until you put that material into another chemical
which brings out the invisible image.
You would start with a much smaller negative
than with a contact printing method.
So at the beginning of photography a negative
has to be the same size as the print you want to make
and that’s because they’re contact printed.
The negative is actually touching the paper that becomes the final print.
As photography progresses we become able to enlarge a negative.
You can put it into an enlarger and make a bigger print
It’s no longer contact printed.
In 1888 George Eastman came out with the Kodak camera
You no longer had to be a professional and know the chemistry
you could actually do it yourself.
It sounds really simple, you know, just send it to us
you press the button, we do the rest
and suddenly invents an entire new industry.
This is the oldest known Kodak camera.
It’s called the Kodak.
It’s serial number 6, meaning it was the 6th one made.
After all 100 exposures have been made, the camera
would be shipped back to Rochester for processing and reloading
Shutter release was on the side
Still works, not bad for a camera made in 1888.
Because the camera was smaller and easy to carry now
People took their cameras everywhere.
It opened up a field of photography for the general public.
For anyone to capture all the different moments of their life.
The basic aesthetic of a gelatin silver print is a smooth surface
because the gelatin sits on top of the paper, and the gelatin is what holds the image material in it.
As opposed to the salted paper print
where the image material was sinking into the fibers of the paper.
The gelatin silver process was the dominant photographic process of the 20th century.
The vast majority of the analog photographs that
we are familiar with were made with this process.
The clarity and sharpness of the black and white
gelatin silver print became the norm for photojounalism.
It was the standard way that information from far away
was produced and sent to be published in newspapers and magazines.
The process became forever linked with the documentary style of photography that was
established by photographers like Lewis Hine, and FSA photographers such as
Dorothea Lange and Walker Evans.
Silver gelatin allows you to make black and white images.
It is responsible for all the movies you have ever seen, that is all silver gelatin.
When George Eastman came out with the Kodak
they started making flexible transparent film about 1889.
Once you have a flexible medium, motion pictures becomes possible.
Gelatin silver is also responsible for color photography.
During development the silver releases dye
and during fixing you get rid of the silver but the dyes remain.
All of the color photographs you have ever made
everything in the 20th century that was color
had silver and gelatin in that emulsion, and that is
really what is becoming obsolete by the digital process.
The shift from analog to digital photography has been going on a long time.
2004 was the high water mark for film production.
After 2004 you really start to see the sales of digital cameras taking over film cameras.
I teach public workshops in photographic processes here at George Eastman House
We just recently declared that silver gelatin emulsion is a historic process.
So now we are teaching people how to make
dry plates and photographic paper from scratch.