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  • 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 thetissuebut 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.

One of the major themes in photography

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B1 中級

顏料工藝--攝影工藝系列--第8章,共12篇。 (The Pigment Processes - Photographic Processes Series - Chapter 8 of 12)

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    Chihyu Lin 發佈於 2021 年 01 月 14 日
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