You are right that there is too much noise when you measure changes of few fF but when using capacitive sensors capacitance change is usually 1pF or more and in this range it works very reliably so it is usable to get maybe.. 10 or 50 pF measuring resolution.
~fF Capacitance measurement with mTouch 16f707 touch button!
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You are right that there is too much noise when you measure changes of few fF but when using capacitive sensors capacitance change is usually 1pF or more and in this range it works very reliably so it is usable to get maybe.. 10 or 50 pF measuring resolution.