Voltage Divider Multiplier Value Too High?
Your setup won't be very good at high frequencies. I guessed at some of the scope probe and scope values, but with the circuit below, the bandwidth is only about 40 kHz. I haven't accounted for all the parasitics, it could be worse. 

If you need higher bandwidth than this, you can buy 1000x high voltage scope probes. 







simulate this circuit &ndash; Schematic created using CircuitLab