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Images © 2007 Steven Keirstead Photography. Images: All Rights Reserved
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Revised 3 Part RA4-Compatible Developer Formula (3/2007) by Steven KeirsteadDownloadable PDF for PrintingThis is a revised formula with pH of 10.3 slightly more basic than the Kodak standard of 10.1-10.2 for RA developers. It is made in three relatively stable concentrates that can be made ahead of time. I have noticed adding 10% Ethanol to part B reduces the chances that microorganisms will grow in it and speeds CD3 dissolution. This is similar to Kodak's RA-4 developer but has different concentrations (to increase developer activity), and does not have an optical brightener. This formula produces best results with Fujicolor Crystal Archive Type P and C with good colors and dynamic range from black to cool white base, and very good results with Kodak Endura Portra, Supra and Ultra papers, with good blacks and a slightly warm white base. I have not tested it on other papers yet. Keep in mind that color balances with this recipe will probably be different than with a commercial formula, I find I need additional Magenta and Yellow filtration compared to Kodak RA Developer. Most of the chemicals are available from Artcraft Chemicals or ArtChemicals.com. You may be able to buy Etidronic acid, Diethylhydroxylamine and Lithium polystyrene sulfonate from Sigma-Aldrich Chemicals or other suppliers. This formula is "open source," so feel free to use or modify it at your own risk. Developer Part A - for 10 X 1.85 Liter batches:
Developer Part B - for 10 X 1.85 Liter batches
Developer Part C - for 10 X 1.85 Liter batches:
For 1.85 Liter of Working Strength Developer, mix:
Some people use a 2% Acetic acid stop bath between the Developer and Blix to minimize mid-tone staining on Kodak RA4 papers, but I have not found this to be needed in my roller transport machine. So long as the Blix is slightly acidic (it should be pH 6.5-6.3, no lower, according to an expert) I do not get staining. If you have trouble with staining, try Developer in Bath 1, 2% Acetic acid stop bath in Bath 2 and Blix in Bath 3. For tube and tray processing or Nova processors, I would recommend the use of a stop bath. RA4-Compatible Bleach Fix- for 1.85 Liters of working strength: This formula is also "open source." Use or modify it at your own risk.
Adjust pH to 6.5-6.3, if needed. This Blix lasts fairly well, and can be replenished with itself. I generally use 25% new + 75% old blix for a day's printing session of 20-50 8-10" prints. If you are heavily using, replenish 50% new + 50% old Blix. Be careful to not let the solution get saturated with silver or silver metal flakes will precipitate onto your paper and equipment, and it's a royal pain to clean up. After 4 to 6 day-sessions of use, I start an all new batch of Blix. I use Blix at 37˚ C, but it should work at lower temps too. |
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Steven Keirstead Hac Facit MMVII, Copyright 2007, Text and Formulas: Re-use with Attribution Allowed. |