Learning about photography

Learning about photography

Invented by Fox Talbot in September of 1840, the Calotype or Talbotye was an early innovation in photographic processes. Until that time, photographers could not “fix” the images on their medium. The process of fixing is making the image permanent, without this process the image would continue to be exposed and darken under exposure to light. During this time. there was a race to become the first to create an image that would become permanent on the surface they were captured.
Here is an example of a Calotype process on one of my own photographs. This shot was taken at Elkhorn Slough in Moss Beach Ca. on a recent walk. I processed it in a variety of software applications including photoshop to achieve the resulting effect.    I am working to refine the effect and may post a tutorial on the process in a future blog entry.

From the Museum of Oxford University:

“The Calotype proper is a negative image (along with its offshoot the waxed paper negative), although its positive counterpart, the salted paper print, is the more common form in which it is encountered. Calotypes are made by brushing the best quality drawing or writing paper with a solution of silver nitrate, drying the paper, and then immersing it in a solution of potassium iodide to form a light-sensitive layer of silver iodide. Immediately before use the surface it treated with ‘gallo-nitrate of silver’ (a mixture of silver nitrate solution and gallic acid) to act as an accelerator. Exposure in a camera, where the paper must be held in a dark slide, produces a latent (invisible) image which is developed by washing in gallo-nitrate of silver, fixed in hypo and thoroughly washed. The translucency of Calotypes can be improved by waxing, and a positive can be made by repeating the original process or by ‘printing out’ the image in much the same way as making a Photogenic Drawing. When toned, in, for instance, gold chloride solution (to give it a purpleish tone), a positive produced in this way is known as a ‘salted paper print’.

You can read more at:  http://www.mhs.ox.ac.uk/features/ephotos/ctypes.htm There are some examples of Calotypes there as well.

While I generally don’t link to wikipedia, here is a decent article on the history of the Calotype process. http://en.wikipedia.org/wiki/Calotype

I challenge you to recreate the look and feel of the Calotype on one of your images and share it. Don’t use one of the automated applications, if you do the work to recreate the look yourself you will get much more out of it. It will force you to not only look at your images, but images from others in history and figure out how to recreate that look in photoshop.