Abstract: A detecting apparatus is to at least assist in determining the concentration of colorants within a carrier liquid. The colorants at least absorb light and/or diverge light. The detecting apparatus includes one or more light sources to emit light, and one or more light detectors to detect light. The light sources and the light detectors are positionally configured in relation to one another such that both light directly emitted by the light sources and that has not been absorbed or diverged by the colorants, as well as light diverged by the colorants within the carrier liquid, are detected and/or determined. The concentration of colorants is determined based on the light directly emitted by the light sources that has not been absorbed or diverged by the colorants and/or on the light diverged by the colorants within the carrier liquid.