Love at first print, more than a half century ago I made my first B&W print from a projected 35mm negative (Kodak plus-x pan) on 4″x5″ Dupont Velour Paper in a not so light tight closet. This combination of projected negative and Silver Gelatin emulsion represents the overwhelming majority of my work produced it the past 50 years. It remains today as my primary print process.

Commercially produced or Personally Hand Coated in my lab, the essential ingredients remain same, the difference is the unique personality of each print.

The combination of silver salts and gelatin quickly became the preferred medium of photographers in the 1870’s due to the emulsion’s sensitivity to low light … by comparison to other processes of that era that required long exposure to daylight. This process advantage allowed the projection (enlargement) of the camera plate to a larger print. Prior to this discovery image size was 1:1 to camera and plate size.

The use of direct contact printing has regained popularity due to the ease of making digital negatives from low cost consumer grade inkjet printers.  …. more on this in another section.

From National Gallery of Art.

The platinum print process is based on the characteristics of light-sensitive iron salts, which react with platinum salts to form platinum metal. A sheet of paper is coated with a solution of these salts to make it sensitive to light. Once dry, the sensitized paper is exposed to light through a negative, developed in a chemical solution, cleared, and washed. The print’s hue may range from charcoal gray to sepia depending on the chemical properties of the sensitizer and developer. Various image hues can also be achieved by adjusting the moisture content of the sensitized paper and/or the temperature at which a print is developed. Further chemical additions to the sensitizer and/or developer provide seemingly endless options for fine-tuning the appearance of the photograph.

The first commercially manufactured platinum paper was introduced in 1879 by British inventor William Willis Jr., who perfected the process over the following decades, gradually expanding the variety of his Platinotype Company products. A chemical variant of the platinum process was introduced in 1887 by Austrian Giuseppe Pizzighelli and marketed by several manufacturers in Europe and the United States.

Unlike a gelatin silver print, the image in a platinum print is absorbed directly into the paper, taking on its characteristics. Thus, the paper upon which a platinum print is made affects the quality of the image. An untreated paper will yield a matte print with a softer and less-detailed image than one made, for example, on a paper that has been chemically modified to impart a sheen, such as the Platinotype Company’s Japine papers, first introduced in 1906.

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From Wikipedia

Platinum prints, also called platinotypes, are photographic prints made by a monochrome printing process involving platinum.

Platinum tones range from warm black, to reddish brown, to expanded mid-tone grays[clarification needed] that are unobtainable in silver prints.[1][dubious – discuss]

Unlike the silver print process, platinum lies on the paper surface, while silver lies in a gelatin or albumen emulsion that coats the paper. As a result, since no gelatin emulsion is used, the final platinum image is absolutely matte with a deposit of platinum and/or palladium, its sister element which is also used in most platinum photographs absorbed slightly into the paper.

Platinum prints are the most durable of all photographic processes. The platinum group metals are very stable against chemical reactions that might degrade the print—even more stable than gold. It is estimated that a platinum image, properly made, can last thousands of years. Some of the desirable characteristics of a platinum print include:

The reflective quality of the print is much more diffuse in nature compared to glossy prints that typically have specular reflections.

A very delicate, large tonal range.

Not being coated with gelatin, the prints do not exhibit the tendency to curl. The darkest possible tones in the prints are lighter than silver-based prints. Recent studies have attributed this to an optical illusion produced by the gelatin coating on RC and fiber-based papers. However, platinotypes that have been waxed or varnished will produce images that appear to have greater D-max than silver prints.
A greatly[quantify] decreased susceptibility to deterioration compared to silver-based prints due to the inherent stability of the process and also because they are commonly printed on 100% rag papers.
Many practitioners have abandoned platinum and only use palladium. The process using palladium alone (sodium tetrachloropalladate) is similar to standard processes, but rather than using ferric oxalate plus potassium chlorate as the restrainer (which is ineffective for palladium), a weak solution of sodium chloroplatinate is used instead. Sodium chloroplatinate, in contrast to potassium chlorate, does not cause grain. This formula is generally referred to as the Na2 method. This somewhat misleading abbreviation was coined by Richard Sullivan of Bostick & Sullivan, one of the principal suppliers of chemistry and printing supplies, who popularized the process.

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Something new something old and something borrowed. This is a hybrid process of transferring a digital asset (image data) to a light sensitive material… in this case the digital data is transferred to a silver gelatin emulsion by light. The aesthetic qualities of the print are that of traditional “light-film-lens-paper” processes with no perceivable variation between prints, making every print “the same”. I offer this print from original camera film images that have been converted to a digital image format. The image is then worked to the same parameters as would be available in the darkroom… crop, contrast, localized lightening and darkening and spotting. I do not introduce new image elements that do not exist in the original camera film. This process eliminates variation between each print, hence, each “DIGITAL SILVER PRINT” is a reproduction of the original.

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