New Physical Developer Formulation

[Heather Baxter]

My lab uses a physical developer kit that we order from Evident. We needed some additional Solution B and when we went to order it, we found that the formulation of the physical developed kit from Evident has changed. After some research, we were informed that the person who originally came up with the physical developer formulation has recently changed it. Now, instead of two solutions, there are three. We were told that the new formulation is more sensitive.

We think that the change might just be through Evident, as the Lightning Powder website still has tech notes for the two solution formulation.

Has anyone used the new formulation yet? What were the results? Any help is thoroughly appreciated.

[David Grady]

After years of using pre-made physical developer formulas, we began making our own. I've found that our results have improved significantly and I'd recommend that any lab that is able to make their own, do so. We currently use the Secret Service formula, which uses Malic Acid, as apposed to Maleic Acid. Actually, they have a newer formula, but so far, we haven't been able to tweak it enough to get it to work as well as their previous formula.

PD formulas are highly sensitive to the water that is used. The Secret Service uses RODI water; we use twice distilled, DI water. Any change in waters will likely require an adjustment in the ratio of detergent.