We generally don’t like going beyond 24mm for wideness on video, and even at 24mm when things come to close to the lens they start to appear abnormal in a way the viewer will notice. Yet one cannot make hard rules for film making and ultrawides can produce speciality looks as like seen here:
Laowa recently received acclaim for their 105mm F2 STF lens. They have followed up with another lens, a 12mm ultra-wide angle that claims to be corrected for distortion.
For video we don’t usually go much wider than 24mm but some may find special applications for this lens. See the following two videos for examples of the moving images it can create:
You can view the Laowa / Venus Lens website for more information.