Not the usual thing for us, but the Construction Historian thinks this definitely counts as a (niche?) part of construction history.
Construction History Society
Orson Welles dug trenches into studio floors on CITIZEN KANE so cameras could shoot up at characters from below ground level. Almost no film then showed ceilings as the space above was reserved for lighting. Welles built ceilings out of muslin so mics could sit above them.
