This paper reports on the development and tests of a new stable film developer that can fully exploit all the inherent speed in the newer thin emulsion, high resolution, high contrast films such as Kodak Technical Pan and Aerographic II, and do this at a low contrast and in the short development times necessary for routine large tank processing. The concept exploits the super additivity of phendione-hydroquinone to push process the "toe" for shadow details. The contrast is held down by reducing the flow of replacement developer through the emulsion to the highlight portions of the negative and by controlling the activity of the hydroquinone by alkaline buffering. Effective exposure index (EEI) is greatly boosted over ASA or A FS speeds by placing an early bump in the D-Log E curve.
Frank B. Gorman,
"Film Processing For Maximum Sensitivity At Moderate Contrast", Proc. SPIE 0354, Airborne Reconnaissance VI, (25 August 1983); doi: 10.1117/12.933997; https://doi.org/10.1117/12.933997