A. 
B.Digital Non-Silver Processes
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Matthew F. Shapoff Interactive Telecommunications Program Thesis Documentation May, 2000 Updated Feburary, 2007 |
Thesis Summary
The final product of the Thesis has been the production of course materials and other tools to teach a class in "Digital Non-Silver Processes". Accordingly, several workshops where held so that the core materials could be defined and the exercises fine tuned.
Early work on the foundation of this process had begun for me during my undergraduate work at New York University’s Tisch School of The Arts photography program. Although not encouraged, I decided to explore my ideas and see what happened. Although I was pleased with the results, it would take years until I had the system perfected enough to teach others.
The main reason that most felt I could not use digital imagery with non-silver techniques was the lack of a contact sized negative, a requirement for most non-silver techniques. With some slight changes in the chemistry and some creative output from the computer I was able to prove them wrong.
During the course of this document the reader will be exposed to many ideas coming from seeming dissimilar camps. The ability to create an artistic, one-of-a-kind image with tangible physical qualities from a pure set of ones and zeros inside a computer has intrigued me, and forced me to look to many sources for answers. Examples will be shown using this technique to create images that range in content from downloaded images from the web of the planet Mars and old New York, to modern day frame grabs from DV tape and digital cameras.
Topic Summary
The area of Non-Silver Processes dates back to the late seventeenth century, with the late 18oo's seeing the perfection of silver based processes. In order to increase the "resolution" of the early processes, silver nitrate was discovered to react quickly when exposed to light. Quick exposures allowed the camera to capture time more accurately. When exposures took hours, people were rarely captured since they would move through the frame quickly enough not to leave an impression. (chapter 1, Parisian Views)
During the development of film based photography the idea of resolution has taken on many meanings. In the 1830's Fox Talbot and several other artists dealt with the issue in regards to the process being too slow. In his situation, details such as people were lost during the long exposures required to fix light over time. By the 1890's photographers like Alfred Stieglitz were using perfected processes and could focus on the content.
We stand at a similar point in the history of digital photography. Now resolution deals with how much information we record within a specified grid. High resolution digital cameras such as the megapixel generation provide over a million pixels of information per image and burst rates equal to autowind film cameras.
To date, the Daguerreotype, a process perfected in 1939 by Louis Jacques Mande Daguerre, has the most detail of any other recording medium.
In 1835, so the story goes, he put an exposed plate in his chemical cupboard, and some days later found, to his surprise, that the latent image had developed. Daguerre eventually concluded that this was due to the presence of mercury vapour from a broken thermometer. This important discovery that a latent image could be developed made it possible to reduce the exposure time from some eight hours to thirty minutes.
Although its resolution, by traditional terms, is limited by the time necessary to make an exposure. A Daguerreotype can be inspected with almost microscopic detail. To that extent everything which remained still during the exposure is rendered with great detail, while moving things are blurred or non-existent. A typlical exposure would take 30 to 45 minutes on a beautiful day, a fact which all but precluded natural looking portraiture. A classic example of this is below (A.) In it you see1839 Paris, seemingly empty except for one soul who stopped to get his shoes shined (B.).
A. B.
Silver based films allow the fast imaging necessary to capture the wings of a humming bird and with physically large negatives high resolution images can be produced. With the introduction of digital photography / videography and its marriage with traditional photography both have gone through similar evolutions. Many terms used in both fields, like the term "resolution", have also undergone changes in meaning.
Pixels can be thought of as analogous to film grain, but are composed of ones and zeros, not crystalline structures. Through the use of a laser writer and acetate I can achieve results which mimic traditional methods of creating a contact negative. After practice and diligence the reader will appreciate this difference between pixel resolution and film grain.
What Is This Whole Non-Silver Thing?
In order to increase the "resolution" (speed in todays’ terms) of the early processes, silver nitrate was discovered to react rapidly when exposed to light by visually darkening. This allowed for quick exposures which captured time more accurately.
Daguerreotypes involved a process known today to be very toxic as are many of the early processes. The uniqueness and beauty of a Daguerreotype are unparalleled in any other process despite it’s "resolution" problem. In many portraits you see in this medium the subjects look tortured. This is due in part to having to hold their pose to unnatural periods of time. Yet nature imagery could be examined with a magnifying glass proving deeper and deeper insights, all in perfect focus and minute detail.
During the mid 1800’s many different people experimented with creating ways to quickly and accurately capture a variety of subjects. Several of these processes required a negative impression of the image to be fixed on a transparent medium such as glass. This was usually done in camera and the plate then processed in the dark until the negative image is fixed on the glass. The glass would then be sandwiched with a sensitized piece of paper and exposed to the sun. A proper exposure would yield results that were both pleasing and as durable as the sensitized medium.
Specimen #1 is a modern cyanotype of a glass plate negative from the 1940’s. This image of my grandparents was passed down from my Aunt with the agreement that I would make reproductions for the family. Over the years I have collected many glass plate negatives , some dating back to the 1890’s, under the same agreement that I would create paper prints for the people who gave them to me. This has been a wonderful experience and has given me the knowledge to deal with many problems one might have when working with contact negatives. Glass plates break, the emulsion eventually starts to separate from the glass, and worst of all they were rarely exposed perfectly. It was from working with these plates that I started to form the requirements for creating the perfect negative for this process.
The Starting Images
Specimen #2
is an image of the Croton Reservoir located where the New York Public Library now sits. I found it during my research at http://projects.il t.columbia.edu/seneca/Images/Svsl09.jpg and downloaded it to my local drive as a GIF file. The process which I then took the image through will be described in a later chapter. A JPEG file could also have been used, as well as most file formats photoshop can interpret.Specimen #3 is an image of a computer generated rendering of a subway system I did two years ago. This space never existed in reality, yet through my process you can touch and examine as if it where a picture of a mountain or the Empire State Building. The process which I then took the image through will be described in a later chapter.
Specimen #4 is a composite of four images all shot on miniDV with a Sony TRV900 in photo still mode. The camera in this mode will produce JPEG compressed images at 640 x 480 pixels at 72dpi. Although not optimum for an 8" x 10" enlargement, at 4" x 5" the images look great when a proper exposure in achieved, a process which will be described in a later chapter.
There are dozens of other specimens in my collection with sources spreading from television captures to sun prints to glass plates. The four specimens provided with this paper encompass all the points and features to illustrate my process and give the reader a tangible product to examine and study.
Working with Photoshop
I have been using Adobe Photoshop since version 2.1 on both the PC and Mac sides and belive it to be best suited for our needs. We will use Photoshop’s image editing capabilities to manipulate our images to create suitable negatives for contact printing. This involves sizing the images to your desire, inverting the image and then converting the image to grayscale.
Sizing the image is determined by the parameters the image was captured at. In my experiments the TRV900 made images that worked perfectly when sized to 4 inches high by 5 inches wide. Many of those images also enlarged to 8 inches wide by 10 inches high as well as all of the images taken with a megaPixel camera. Images taken from the web need to be examined to determine how large they can be made. Specimen #2 was a 1.2mb file allowing me to print at a full 8 inches high by 10 inches wide.
Once the image is open in Photoshop, and cropped to your desire. Choose:
Image->Adjust->Invert
this will provide you with a basic negative.
Next choose:
Image->Adjust->Levels
Here, you should move the window away from covering the image, then choose the blackpoint eyedropper and select the area which you would like to be your brightest white.
Do the same with the whitepoint eyedropper for the area which you would like to have the darkest of the dark shadows.
This will come with experience, as images are sometimes considered flat when they do not have enough gradations between the brightest white and darkest dark. If your prints suffer from lack of contrast, consider adjusting these settings more dramatically. If necessary, increase the canvas size of the image and draw a gradient in the new space. Then sample your dark and white from that scale and watch how the image changes. This technique has revitalized many flat images given to me by others.
Next convert the image to grayscale:
Image->Mode->Grayscale
ok the confirmation to discard all the color information.
Printing To Transparency
Instead of transferring our image to a glass plate or cellulous, we will use acetate and a laser printer. Most office supply stores sell materials meant for overhead projectors. I have used both acetates meant for inkjet printers and laser printers, and have found that negatives created from the laser printer are much more durable and can produce 20+ prints before they start to degrade.
I have concluded that 300DPI is just fine for this process. I suggest choosing a paper that has enough of a tooth (texture) to cover the dots used by the laser writer to re-create the grayscale negative on the acetate. Most printers have a choice of dot pattern, I have found the scatter dot pattern to be the best choice and is usually unnoticeable in the final print. The higher the resolution (DPI in this case) of your printer the finer the scatter pattern can be.
Sensitizing The Paper
Appendix I is the handout I circulated after the students requested a detailed description of how to sensitize the paper. The process involves two compounds: Ferric Ammonium Citrate and Potassium Ferracyanide in a ratio of 1:2:10 with the 10 being water. The mixture is then painted onto paper, cloth, anything you like that will hold the coating. Dry the paper in a cool dark place, like a basement or kitchen cabinet.
When the paper is dry it will have a yellow/green color. Sandwich the paper sensitized side up (yellow/green side) with the negative emulsion side up. If the image comes out flipped (ie. type is reversed) you didn’t have the emulsion side, no problem, explore again.
Exposure
Take the sandwiched glass and sensitized paper clipped firmly in place, outside into the bright sun light. On a nice day in New York an exposure can happen as quickly as 5 minutes.
http://greatbasinphoto.com/images/frames4.jpg
This kind of frame will allow one to open the frame and check the sensitized paper. When the image on the paper has not only appeared but the shadows have reversed, it’s time to wash the print. These frames replace many of the multiple iterations trying to get exposure right. Using the sun can prove a challenge as it is rarely the same intensity or color quality for very long. I use simple glass plates and particle board with bull nose clips to sandwich my materials. I find this to be economical and allows me to unclip one side and peek in. The important thing is to keep the negative and paper in register, any shift in the image will either blur it or create multiple impressions.
Evaluation
After an exposed print is dry it can be evaluated based on several of the criteria below. A proper print will have dark blues in the shadows, the color of the substrate (the paper, cloth, etc. that you coated with the chemicals) as the highlights and many gradations of blue in-between. This can be adjusted in Photoshop when creating the negative by setting the dark and white points at their extremes. The details should be sharp, if they are not the sandwich may not have been tight, or the original image may be soft. Photoshop can sharpen many images to a suitable level that once printed the image looks great. If stains appear in the print, try pre-washing and drying the substrate before coating it with the sensitizing solution. Also make sure your application instrument is clean, I rinse my brush in fresh water between each piece of paper.
Conclusions
For the past 10 years I have been able to pursue these endeavors without the use of a darkroom. An Apple G4 with a GCC laser printer was used for most of the recent images, but the original machine I started these investigations on was a Macintosh IIci with a Personal LaserWriter. It has been great to be able to continue to print photographs in an economical way that is friendlier to the environment than silver based photography. Appendix II is a course outline which will be used when I get the opportunity to teach the materials I have created. Film grain will never be replaced by dot patterns, but as modern day CMYK printing illustrates, many line screens are hardly distracting and often unnoticeable to the untrained eye. With the proper choice of paper, the dots completely disappear and an enjoyable, tangible keepsake results.