The photogenic drawing

The photogenic drawing is a type of image making that uses silver nitrate and salt to create a positive-negative image on the exposed surface. Invented by William Henry Fox Talbot, the photogenic drawing was announced after the discoveries made by Daguerre with his own photographic process. Being reasonably inexpensive and simple, the photogenic drawing was a great advance in photographic image making, the process using basically the same end product that black-and-white photo paper is today.
With the light sensitive silver nitrate applied to the paper, an object or a negative is placed on the surface and allowed exposure until they seemed done, about 5 minutes depending on the mixture. Another method was placing the paper in a camera obscura, also giving an image.



The Procedure
In our experiment, we created our own photogenic drawings, and tested the varying sensitivity to light that different mixtures of chemistry would have.

1. 100% rag paper was labeled and adhered to a cutting board with masking tape for stability and organization
We labeled 12 sheets for different ratios of salt (NaC)l and silver nitrate (AgNO3), and different number of coatings of each
These are the mixtures used:
1. 1 coat 2% NaCl and 2 coats 12% AgNO3
2. 1 coat 2% NaCl and 2 coats 5% AgNO3
3. 1 coat 5% NaCl and 2 coats 12% AgNO3
4. 1 coat 5% NaCl and 2 coats 5% AgNO3
5. 2 coats 2% NaCl and 2 coats 12% AgNO3
6. 2 coats 2% NaCl and 2 coats 5% AgNO3
7. 2 coats 5% NaCl and 2 coats 12% AgNO3
8. 2 coats 5% NaCl and 2 coats 5% AgNO3
9.2 coats 2% NaCl and 1 coat 12% AgNO3
10. 2 coats 2% NaCl and 1 coat 5% AgNO3
11. 2 coats 5% NaCl and 1 coat 12% AgNO3
12. 2 coats 5% NaCl and 1 coat 5% AgNO3

2. Salt solution was applied with a brush and then allowed to dry, either 1 or two coatings
3. Silver nitrate solution was applied with a brush and allowed to dry, either 1 or two coatings
4. A variety of objects were placed upon our paper, including a zippo lighter, car keys, scissors, and pens
5. The paper was set outside in daylight for a 7 minute exposure time, and then brought inside
6. The sheets were peeled from the holder, washed in strong salt water, and then washed in cold water.

Results

We found that more salt is bad for the paper, as it gives less sensitivity to the silver, and the resulting image is very light, where too much silver or not enough salt leads to a dark, overly sensitive and ugly image.



Here are more resources on the subject:
http://www.mhs.ox.ac.uk/features/ephotos/pdtypes.htm
http://www.sugimotohiroshi.com/PhotoDrawing.html
http://www.edinphoto.org.uk/1_early/1_early_photography_-_processes_-_photogenic_drawing.htm

Anthotypes: First Project

Photograph by SILVINO GONZÁLEZ
Check him out: http://bipolaryourmung.wordpress.com/2010/12/16/anthotypes-update/

Our first topic in class was the anthotype: an image making process developed by Sir John Herschel in the early 1840's. The process paper to be coated with a light-sensitive extract obtained from various organic material, more commonly leaves and berries, and exposing the coated surface to light with a desired image overlay, creating a contact print. The name is derived from the Greek word antho, meaning flower. For the completely exposed surface of the paper, color will bleach away as the sunlight destroys the color of the juice. The covered part of the surface will not be exposed to the UV rays of the sun, and the color will remain, resulting in an image with a positive image. While the exposure takes a long time, the resulting image can be quickly destroyed if exposed to more sunlight, due to the now vulnerable and previously-protected coating.

Lab work: In my class, my team and I created an experiment to test what light sensitive materials: Raspberry or spinach juice; and which binder: water or alcohol; would create the best image when used as a coating for an anthotype.

The process involved 2 coats of light sensitive material on 6 sheets of bristol board, using 6 different coating mixtures:
1. Sheet one was coated with a ratio of 1:1-filtered raspberry juice and distilled water
2. Sheet two was coated with a ratio of 1:1-filtered spinach juice and distilled water
3. Sheet three was coated with a ratio of 1:1-filtered spinach juice and filtered raspberry juice mixture, and distilled water
4. Sheet four was coated with a ratio of 2:1-filtered raspberry juice and alcohol
5. Sheet five was coated with a ratio of 2:1-filtered spinach juice and alcohol
6. Sheet six was coated with a ratio of 2:1 - filtered spinach juice and filteres raspberry juice mixture, and alcohol

7. All sheets were covered in some locations, covering the different coatings
8. Sheets distributed to group members
9. All sheets were set up and places in sunlight for exposure.

I received the sheet coated with 2 parts spinach juice, and 1 part alcohol. I placed a cut-out of a supermodel on to block some light and allow other light to expose the coating. I placed it in a window that gets the most light in my house, and taped a black board behind it to prevent strange reflections through the glass. I hope for an image of a bikini-model within the next few months.

Here is an image of my current set-up:




Hopeful!

Here are some good links to learn more about the anthotype process, and help you make your own:

http://www.alternativephotography.com/wp/processes/anthotypes/anthotype-process

http://193.166.40.90/?cat=18

http://www.f295.org/Pinholeforum/forum/Blah.pl/Blah.pl?m-1187767675/