Fluorescence quantum yields (FQY) are important measurands of dye molecules. Commonly, they are determined by comparisons with standards. Many standards have FQYs of around one. Often one encounters FQYs of 10^-4 or even lower. Determining these yields with common standards is like measuring (sub-)millimeter length with a folding ruler instead of a caliper. In a recent publication, we introduce “shorter” rulers for molecules with small FQYs.