Mixing and storing Sepia Toners

I've been mixing my own thiourea sepia toner and bleach for a while now. But I'm starting to question how I'm storing and re-using it.

I'm mixing using the formula in Tim Rudman's book listed as Rayco's formula for a working solution. So I have a 1L bottle of bleach, and three 1L bottles of toners with different amounts of Sodium Hydroxide added. But they are all at working solution amounts, so I can just pour them into the tray and use them. My latest batch is about 3 months old, and I frequently use it.

Lately my colors have been inconsistent and weaker. And I'm wondering now if I should not be reusing the solutions, let alone storing them in a working solution state.

I'm thinking of mixing bleach and toning stock solutions and diluting (usually 1+9) for use, adding an additive to the toner for color and using them one-shot as many of you do. Would this be a better alternative? And could the storing of bleach and toners in the working solution state and reusing them cause rapid deterioration of their properties?

For this type of toner, I usually keep the working solution on hand and discard it when the results take too long, or do not meet my expectations any longer. After a while they will get to the point where they no longer give good results, but that will happen no matter what you do unless you mix up a fresh batch, use it for that session, and then discard it. Given the results you mentioned, it sounds like your ready to mix a fresh batch.

- Randy

I tend not to tone many prints, and consequently the re-developer is never used to exhaustion in one session. I find that it does keep well in a sealed bottle, and I use it until re-development begins to slow down. At that point, I discard the re-developer and begin again. I have not ever used it hard enough, or stored it long enough, that the solution failed to re-develop the image to my satisfaction.