Why do new turbos come with one compressor/turbine fin painted white?

[boredguy77]

just like the title states, I have seen a couple of turbos (including mine) that have one white compressor fin, when brand new, what is this, or rather why? Anyways Thanks for curing my ignorance

 

[DCVING 6]

my guess would be they mark it when they are balancing it.

Anybody know the real answer?

 

[boredguy77]

I was kind of thinking like you were, I bet we are right, just someone that knows for sure needs to confirm it.

 

[The Radius Kid]

Yup,they balance with a strobelight.
You watch the mark and see if it "jerks" as it spins on the test stand.
That indicates where the imbalance is.