Unblinking Eye
                              Pyro Staining Developers - Page 4

 

RECOMMENDED DEVELOPMENT TIMES

CI (contrast index) charts are provided below for a number of films that I have personally tested. The charts are very simple to use. To find a development time for a particular film and process just locate the point on the chart where development time (y-axis) intersects with the optimum CI (x-axis) of the printing process. The development times indicated should give negatives that print well with subjects of normal lighting, what we would refer to as N subjects (in Zone terminology) or SBR 7 with incident metering methods. However, it is important to do your own testing with new developers to determine what development times are needed for other than normal lighting conditions before processing important negatives.

Below are the approximate CI values needed for a number of alternative processes. Most processes have means to control contrast but it is good practice to always start with the best negative possible for the process.

Process

Optimum CI

Silver Gelatin

0.47 to 0.52

Carbon

0.65 to 0.75

Platinum

0.68 to 0.72

Azo

0.70 to 0.75

Kallitype and Palladium

0.80 to 0.85

Vandyke

0.85 to 0.95

Albumen and Salted Paper

0.90 to 1.00



The CI charts below are based on rotary processing in BTZS type tubes, with a pre-soak of five minutes. The time and temperature of development is noted on each chart. The charts that have violet caption and end with the word UV are intended for printing with alternative processes that use UV light for exposure. These charts were created based on a UV reading of the negatives. Charts that have blue caption and that end with the word Blue are intended for printing with silver gelatin processes, including AZO. These charts were created based on a Blue channel reading of negative densities.

Photographers who have established reliable development times for specific films with PMK or Rollo Pyro can use these times as guides for initial testing with Pyrocat-HD. For printing with silver gelatin and variable contrast papers development times for Pyrocat-HD, 1:1:100 dilution, are only about 70% of PMK times, and only 50% of PMK times if developing for a UV sensitive alternative process. When using the 2:2:100 dilution of Pyrocat-HD development times are virtually identical to those of Rollo Pyro at a dilution of 2:4:100.


Figure 8. Ilford FP4+ in Pyrocat-HD, 2:2:100. UV
Figure 9. Acros in Pyrocat-HD, 2:2:100. UV
Figure 10. Bergger BPF 200 in Pyrocat-HD, 2:2:100. UV
Figure 11. FortePan 400 in Pyrocat-HD, 2:2:100. UV
Figure 12. HP5+ in Pyrocat-HD, 2:2:100. UV
Figure 13. TMAX-400 in Pyrocat-HD, 2:2:100. UV
Figure 14. JandC Classic 400 in Pyrocat-HD, 2:2:100. UV
Figure 15. Ilford FP4 in Pyrocat-HD, 1:1:100. UV
Figure 16. Ilford FP4+ in Pyrocat-HD, 1:1:100. BLUE
Figure 17. Bergger BPF 200 in Pyrocat-HD, 2:2:100. BLUE
Figure 18. Kodak TRI-X, in Pyrocat-HD, 1:1:100. BLUE
Figure 19. TMAX 400, in Pyrocat-HD, 1:1:100. BLUE
Figure 20. HP5+, in Pyrocat-HD, 2:2:100. BLUE
Figure 21. FP4+ Pyrocat-HD, 2:2:100. BLUE
Figure 22. Acros in Pyrocat-HD, 2:2:100. BLUE
Figure 23. TMAX 100, Pyrocat-HD, 2:2:100. BLUE
Figure 24. TMAX 400, Pyrocat-HD, 2:2:100. BLUE
Figure 25. PhotoWarehouse ASA 125, Pyrocat-HD, 2:2:100. BLUE



NOTES

1. E. J. Wall and Franklin I. Jordan, Photographic Facts and Formulas, Revised and extensively rewritten by John S. Carroll (1924; Englewood Cliffs: Prentice-Hall, Inc., 1976): p. 112.
2. Stephen G. Anchell, The Darkroom Cookbook (Boston: Focal Press, 1994): p. 175.
3. Steve Simmons, “Review of the Book of Pyro,” View Camera (September/October 1991): p. 23.
4. Information based on personal correspondence with Carl Weese.
5. Bob Herbst, “The Effects of Pyro Stain in Platinum Printing,” View Camera (July/August 1999): pp. 16-24.  Republished online at http://unblinkingeye.com/Articles/Pyro/pyro.html.
6. Phil Davis, quoted in  “The Black and White Corner,” View Camera (January/February 1998): p. 55.
7. Gordon Hutchings, quoted in  “The Black and White Corner,” View Camera (January/February 1998): p 55.
8. Stephen G. Anchell and Bill Troop, The Film Developing Cookbook, pp. 79-80.
9. Ibid., p. 80.

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