One of the major themes in photography
is this desire to have a more permanent image.
You have the woodburytype.
You have the platinum print.
Very stable, very long lasting processes.
Then you also have the pigment family of processes.
The gum bichromate process and the carbon print process.
The gum print is based on the light sensitivity of chromium.
Mungo Ponton is the first person to really do experiments
with the light sensitivity of this compound.
Talbot himself experiments with chromium salts.
He discovers that if you mix them with colloids
gelatin or gum they harden when they are exposed to sunlight.
Based on the work of Talbot it doesn’t take too much time
for people to figure out that if we take a colloid
like gum arabic, and we put pigment into those, and then sensitize those with chromium salts
we now have a medium that can brushed onto paper
expose it to light under a negative
and when we put this paper in warm water areas that
are struck by light will harden, and that’s where the dark pigment will be.
Areas that are not struck by light will dissolve away, leaving the white of the paper.
So now we have a brand new printing process, based on chromium.
If you look at a gum print, the darker the picture, the thicker the deposit of gum.
The whiter the picture, the more you are getting towards the actual paper.
So the image itself will have slight relief.
One of the names associated with gum printing and carbon printing is Alphonse Poitevin.
He is a Frenchman who perfects certain elements of chromium printing.
While it is still imperfect, it is the seed
to an improvement that is later done by Joseph Swan
that results in the process we now call carbon printing.
It is essentially a piece of paper that is coated with gelatin that is bearing pigment.
This thing is called the “tissue” but it is not tissue like at all, it’s like a piece of plastic.
The tissue is sensitized with chromium.
It is then contacted printed with a negative.
The light striking the gelatin hardens it selectively.
The tissue is then put into cold water, and a second piece of paper bearing clear gelatin
on the surface is put into contact with the tissue.
They are slid into a tray with hot water.
The unhardened gelatin with pigment oozes out the edges.
It is softening because of the hot water.
You peal off the original tissue, and by washing it in hot water
you take away all the black you don’t need in order to get a continuous tone photograph.
The image you get is very very permanent.
It is still being done today, there are still people making carbon prints today.
Pictorialists really established photography as a fine art form.
They used things like the gum bichromate process or platinum prints that involved a lot
of hand work and craftmanship.
You really had a sense of the photographic object
as something that was made by somebody.
Alfred Stieglitz is the person most associated with
what was called the photo-secession.
He and Edward Steichen co-founded the movement.
They promoted this idea through a publication called Camera Work.
Stieglitz had a gallery called 291 in New York that showed
photography as an artform.
This was a camera that was used by Alfred Stieglitz.
It was given to the museum by Georgia O’Keeffe in the 1950’s.
The opening of that lens determines the sharpness of the picture.
If you open it up quite a ways, you get an image that is soft around the edges.
He was interested in pictorialist photography, and this was the lens designed to do that.
Stieglitz, Steichen, and Kasebier wanted
people to take photography seriously as a fine art form.
Not just an automatic activity that produced images without anybody’s intervention.
I think what the argument was really about was
where is the creative input of the artist in photography.
That is a theme that goes back to the invention of the medium.