I am using a LegacyPro brand brown toner. This is a one step brown toner (not the bleach redevelop type).
I was told doing this and follow it with a soak to HCA to stop the process. A problem is, the toning process actually seems to speed up in HCA and the color shifts to warm brown with some red in it. In HCA, the color visibly changes.
I actually like the color but it makes the process very difficult to control and get the right amount of toning.
Am I misinformed about using HCA as a stop-bath for brown toner?