If you want to adjust the focus by yourself, you need to loosen the locking ring and twist it slowly until the image on your Monitor/Goggles is focused and then tighten the ring up.
There are two ways to adjust the focus:
1. Install the Split on the drone，While watching the Goggles/Monitor screen, turning the lens until the picture is clear.
2. Connect the camera with the APP，while watching the live preview screen, turning the lens until the picture is clear.
After adjustment, you need to record a video and play it on your computer to see if it is in focus. If not, you need to repeat the above steps several times.