White Mountain Imaging in an effort to assist customers in efficient use of our products has offered the T2 Activator for several years. There have been several questions on the uses of T2 Activator and the relationship between T2 Activator and T2 Starter. There is no relationship between the two products as they have distinctly different functions. They are, however both used at the same point in time… after a developer change over.
Purpose of Starter:
Developer Starter is a chemical mixture designed to make developer replenisher into developer. Developer replenisher is the product created when concentrate developer components are mixed with water to make the replenisher for the processor. Developer starter basically introduces a specific amount of bromide to assimilate the bromide that is produced by reducing silver in film, commonly referred to as “seasoning the developer”. Today the variety of films and improvements in developers requires proper understanding and vigilance in the use of starters. One should only use the starter designed for the particular developer being used. Starter can suppress the activity, increase the activity, or have no effect on the activity of the developer dependent on the particular film being processed. However, Starter is important in balancing the chemistry of the fresh developer to insure stable, consistent performance in conjunction with replenishment.
Starter is often added to “flood replenisher” in the holding tank or mixer to maintain the bromide level and keep sensitometry stable in low volume situations. White Mountain Imaging typically recommends the addition of 1.6 ounces of starter to each gallon of developer replenisher depending on the type film being used. For processing Kodak Min-R 2000 and Agfa HDR-C films, 3.2 ounces of starter should be added. Do not add additional starter to the processor tank.
Purpose of T2 Activator:
T2 Activator was designed as an activity “booster” for T2 Developers in situations where sensitometric activity increases as a developer seasons. If normal sensitometry stabilizes after this increase then the use of T2 Activator may provide stable sensitometry from the start-up. The T2 Activator was designed to temporarily help the fresh developer quickly attain these normal activity levels and thus maintain stable sensitometry and patient exposures.
Activator Use: Activator may be added after T2 Starter in the above-mentioned situations in quantities of 50ml (1.7oz.) per gallon. If more is needed another 50ml may be added. A third addition may be added when required. We do not recommend more than three additions without a 5-day average run with fresh developer without activator but with starter.Download Technical Memo