The average DSLR gimbal running 52** motors or 5108 iPower motors draw about 1.5A to 1.7A on 4S.

Here’s a discharge graph of a 4S 2200mAh lipo pack @ 1.75A constant

Starting from fully charged 16.8V (4.2V x 4) the battery lasts around 30 minutes @ 1.75A discharge rate. The discharge was stopped at 15.4V (3.85V per cell) which is a safe discharge level for Lipo packs.

It’s a good practice to set PID settings when the pack is half way discharged.
In the above example
Voltage drop 16.8 V- 15.4V = 1.4V
Best voltage to set PIDs: 16.8V – 0.7V = 16.1V (half of overall voltage drop:  1.4V/2 = 0.7V )

Remember, brushless gimbal motor performance if directly proportional to the supply voltage. Monitoring voltage  and operating within voltage range will help you achieve uniform results all the time.

* Above test data is provided for informative purposes only. It does not grantee operational times by any means.