Perfect eye lashes with mascara

This has always happened to me when applying mascara: If the mascara is new, you usually get more mascara on the eye lashes than you wanted to, if the mascara is almost empty, you get hardly anything out. And in between it comes out in clumps which is not great.
I now use a almost finished mascara, dunk the brush once into the new mascara, mix it around in a small container and there I have the exact right amount of mascara on the brush.