Betaflight filter settings explained (4.5 / 4.6)
Filters decide motor heat and latency. Modern Betaflight filters dynamically very well — this overview shows what each filter does and where it makes sense to intervene.
The filter chain at a glance
The signal runs through the RPM filter (motor harmonics at the source), the dynamic notch (strongest remaining peaks) and the gyro/D-term lowpass (residual noise). Each stage removes noise but costs delay — so: as much as needed, as little as possible.
Mind the gyro type
How much lowpass you need depends on the gyro: low-noise gyros (e.g. MPU6000) get by with less filtering than more sensitive newer ICM gyros (e.g. ICM-42688). Take the defaults recommended for your gyro as the starting point.
The RPM filter lets you run less lowpass
Because the RPM filter hits the motor harmonics precisely, you can then raise the gyro/D-term lowpass cutoffs (less delay, sharper tracking). Without an RPM filter you have to close down with more lowpass — at the cost of more latency.
Set filters from the log, not the datasheet
The only reliable way is to compare filtered against unfiltered gyro. PIDoctor shows exactly that, measures filter effectiveness and recommends cutoffs that balance noise against delay — for your specific quad, not an average.