> As D-76 ages a chemical compound, hydroquinone monosulfonate, is formed. This chemical compund will INCREASE the activity of the developer and the contrast of your negatives in a big way with T-Max." I wonder if this is not the increased activity that is being attributed to a rise in pH?(posted 8498 days ago)Could be; I'm not a chemist and certainly don't know.
I've seen it explained that the rise in pH activates the hydroquinone, which at normal pH simply regenerates the metol. Grant Haist proposed a simple solution to the problem by eliminating the hydroquinone and slightly increasing the metol, to make D-76H.
But what I'm really getting at is that this is taking on the characteristics of a myth, similar to "fixer sinks to the bottom," with people simply repeating it as common wisdom...and it might not be true.
I'm not questioning the change in activity associated with D-76 mixed according to the formula; that's well-documented. What I'm questioning is the common wisdom that _packaged_ D-76 increases activity with age, given that the packaged version is _not_ plain old D-76. I've never seen anyone make any distinction between the packaged version and the formula version while making the assertion.
The obvious test would be for someone to make up some packaged D-76 and test it, say monthly, with film exposed to a step wedge and the resulting densities logged.