Its hard to measure exactly one dipper because of the granular nature of the powder
In another forum, our tireless expert Chem Geek wrote that the precise amount is NOT IMPORTANT
........you just need to add enough powder to get a decent color. Any extra won't require more drops. Think of the powder as a dye (which it is) -- you need enough to see the color, but the dye is just indicating ANY presence of chlorine while the drops are removing chlorine so having more dye won't matter since it still won't show any pink if there is no chlorine left (because you've titrated it all away).
In fact, after I read this and tested using one dipper and two dippers, the difference was only one drop to get clear liquid.
This seems of interest to many because it means we can use 1/2 as much DPD powder.
Can someone re-confirm that this is correct?