As part of the art department on Avengers: Age of Ultron I designed the Jarvis Vs Ultron lab scenes. Animal Logic VFX Supervisor Paul Butterworth and Producer Jason Bath foster a collaborative creative environment and many of us threw ideas into the ring for the look of both Jarvis and Ultron.
In these scenes Banner and Stark are trying solve the enigma of Ultron and Jarvis is attempting to decode and communicate with this new energy force.
When we receive the shots we have to retro fit the holograms and graphics to Stark's motion. Robert Downey Jr basically waves his arms around gesturing and moving things that are not there. Working this way, in the end gives a really natural look, not overly choreographed.