This quick guide will explain how to calibrate your ESCs so they throttle up evenly.
Joshua Bardwell explains in these two videos why this is important
The general idea is to "program" the ESCs via the flight controller to tell them what the minimum and maximum pulse width is that they should be expecting.
This will only work if you left the Programming by TX
option turned on in BlHeli. If you turned this off, you'll need to enable it first. If you're running a recent version of CleanFight or BetaFlight, you can do this via your flight controller without unplugging the ESCs!
Checkout the Configuration Guide if you need to on Programming by Tx
Open CleanFlight Configurator or BlHeli suite. I will use BlHeli suite in my example, but they both do the same thing.
Connect to the flight controller to your computer, but don't plug in the flight battery yet. We want the flight controller turned on and the ESCs turned off.
Click on the Motors tab
Click the switch or checkbox to enable motor outputs
Drag the far right slider all the way up to output max throttle to all motors.
Turn the motors by plugging in your flight battery and wait for the series of 3 sets of ascending beeps to change to constant-tone beeping. This indicates max throttle has been stored:
Drag the all-motors slider on the far right side of the configurator down to the bottom and wait for the set of 3 descending beep sequences to end indicating a saved min throttle.
Turn off the quad and you're all set!
If you're looking for the optimal settings, checkout the configuration guide.