1. Size of the room and wall
A first and easy criterium, is the size of the control room. For small rooms, LCD is generally the preferred technology. The panels are quite shallow, so the real estate space taken by the video wall is quite limited. What’s more, LCD is also ideally suited for short viewing distances (providing an excellent visual experience even when watched from up close. Good viewing angles () ensure that every operator can comfortably see the content on the video wall, even when they are positioned at the edges of the room. If interactivity is needed (which is most often the case in smaller rooms with a limited number of operators), then LCD video walls are the best option as well.
Rear-projection cubes feel most at home in larger rooms because they need more depth. Operators will have the best optical experience when looking quite straight at the wall. So a mid-sized to large control room, in which operators are positioned a bit further from the wall, is ideal for RPCs.
Direct view LED video walls are also at their best in slightly larger rooms. They are very shallow, so take up very little real estate space, but require a bit more viewing distance, depending on the pixel pitch, for the best effect. A 1.2 mm pixel pitch model, for example, is best viewed from about 3 meter / 9.6 feet. By the way, the optical performance of LCD video walls does not restrict them for use in small walls: they are suited for use in larger rooms as well!