I just shake my head and wonder...why?
For me mixing paint is done using the TLAR method...and I don't use pipettes or eye droppers. Instead I pour or dip a stir stick into the color I want to add and either swish the coated stick into the paint I am mixing up or count the drops as they drip off the stick. No fuss no muss and no difficult clean up.
Kinda like watching Grandma make bread...a handfull of this, a pinch of that and all turns out just fine. Stressing over minute and exacting amounts is to me rediculious, but to each his own. Nothing worse than to have an otherwise enjoyable build turn frustrating over a simple task as mixing paint.
The sad fact is, those who go through this tedious route could take their paint and hold it up to any 1:1 actual item they are trying to replicate with a model and it wouldn't match exactly to any one of them. Paint fades and wears continiously and at different rates...and everyone's eye is different.
I've had a couple encounters with paint snobs who say your shade isn't "exact" as the aircraft portrayed was on the date the photograph and documentation used for the kits instructions. To them I say well Lt. Schniederhoffel plane may have looked like that on that date, but it looked like this the day (before/after..which ever is applicable) that photo was taken. Were you there? Did you see it first hand. Oh, so you saw it in a musuem...was it restored? No, then I assume the paint hasn't changed one iota since it was last flown by Lt. Schniederhoffel some sixty years ago?
Are we talking the difference between black and white or shades of gray here? TLAR...That Looks About Right. Back into the fumes I go!