I fiddled with the picture a bit to bring it up:
and I'm pretty sure that the figure on the right is operating a TV camera. There were boxy movie cameras in the 20's but I'm not aware of any that had a lens turret. Also, the proportions of the (probable) thermostat on the post in the main picture fits that of a Honeywell T42, which was made between 1939 and 1953. Given that, and the mid-century style of the mural, I would date picture to 1950 plus or minus a couple.
Cheers,
Earl