You may be right. On the other hand, the manufacturer might have the instruction wrong but the amount of active chemicals in the bottle just right, with varying water volumes! This is the case with many chemicals. For example, most Kodak color chemicals are meant to be mixed as whole bottles, and they don't give instructions on splitting the concentrates at all, nor they will tell how much there should be.
With Tetenal, who knows? It may be that the instruction is wrong about splitting, and you should have mixed the whole liter at a time without measuring anything; or, it can be that the instruction and concentration is right and they put a wrong amount in the bottle. It has to be either one of those according to your results (and I believe that you didn't make a mistake in measuring), but we can never know which one was the problem, without a chemical analysis.
I stopped using all Tetenal products because of the quality problems in RA-4. This is actually not surprising.
However, I have a "feeling" that the most general way for color chemicals is that the bottles have the actual, correct amount that, when mixed as instructed, will give right concentrations. It should be the way they are designed. Then, splitting may be an extra feature. But again, can't know about Tetenal. Maybe you should ask them.
Last edited by hrst; 04-06-2011 at 06:25 PM. Click to view previous post history.