Here's everything there is to know about UE4.27's In-Camera VFX.
For those unaware, Unreal Engine 4.27 has introduced a number of improvements to the efficiency, quality, and ease of use of Unreal Engine’s in-camera VFX toolset. ICVFX is a new methodology for shooting real-time visual effects during a live-action film shoot. This technique relies on a mixture of LED lighting, live camera tracking, and real-time rendering with off-axis projection to create a seamless integration between foreground actors and virtual backgrounds. Unreal Engine supports this technique through multiple systems such as nDisplay, Live Link, Multi-User Editing, and Remote Control.
Recently, the Unreal Engine team has released a new series of tutorials, exploring all the nuances of the new ICVFX toolset, showing users how the systems within the toolset work, and explaining how to use the toolset in virtual production. You can check out the entire series here.