This package of Bergger P.M.K. Photographic Film Liquid Developer 250ml A + 500ml B will make 25 liters of working solution.
Short Historical Aspect
Pyrogallol was the most popular developer in the 19th century. Although it was considered the best developer, it was difficult to use. With the discovery of easier to use developing agents such as génol (1891), pyro began to lose popularity. Nevertheless, in the 20th century, photographers such as Edward Weston used pyro developer in the tradition of fine art. Nowadays, the constant search for improved technique in the expressive craft and fine art aspects has created a renewed interest in the use of pyro.
Aesthetic Advantage of P.M.K.
Pyro can provide a definite increase in both the printing quality of the negative and its capacity to record subtle differences of light. Sharpness, acutance, highlight separation and the masking of the inherent grain, are properties of the negatives that show immediate improvement.
Pyro reveals its magic when processing film used in photographically difficult or subtle light conditions. Early morning, late evening, bright lights, strong backlight, very detailed highlights and all atmospheric effects will be enhanced by pyro developer use. Acutance and tonal separation are more evident throughout the negative image. Because pyro affects film differently than other developers, the elements of the film/developer relationship are important.
Pyrogallol, solution A and solution B, is made with Sodium Metaborate. After a week or two, the color of stock solution A will turn a pale yellow colour. This is the equilibrium point and no further change will occur.
The shelf life of the stock solutions is exceptional. Partially filled and stored bottles will last 10 years or more.
Working Solution of PMK
1 part A + 2 parts B + 100 parts of water = working solution
Example: 10 cc A + 20 cc B + 1000 cc of water make approximately one liter working solution (1030cc). Measure the quantity of water and add the A and B stock solutions. It does not matter which is added first.