is it possible to use the 12v lead coming out of the IRIS’s bottom to not only power a gimbal (in my case a DYS 3 axis gimbal) but also power a video tx (in this case, a Fatshark 5.8 Ghz 250mW), or it is strongly recommended (for what reason ?) to get another separated power lead ?
The voltage from that cable in the Iris is unregulated battery voltage, so powering the video system from it can cause noise from the motors to the video signal. A DC - DC regulator might help.
Thanks for the feedback. When you say a DC to DC converter, do you mean a ubec?
Yes, an UBEC should work, just use the one with the proper voltage output for your video transmitter.