I'm currently working on a redesign of a system that visualizes mocap data and am wondering if I should follow suit.
This article goes into some detail about dark and light themes. It makes good points about contrast between content, controls and background. Allowing more focus to the important bits.
Most 3D computer graphics software such as Blender and product design and prototyping tools such as UXPin, come with a dark theme option. That’s not a thoughtless decision of design. Such tools can be quite complex and intimidating with the amount of functionality options available to the user. The dark theme can let all of those options sit in the background and not appear as intimidating, while shifting the focus to the main content area — the mesh of a 3D object or the elements of a mobile app design.
It could also be a consideration of the users' environment, maybe motion caption guys only work at night like Batman...