For those of you have never been on a movie studio lot, this photo of the Warner Bros. studio lot gives you an idea of how cavernous the soundstages are. And they need to be. One week they could be housing a Roaring Twenties speakeasy, the next week a pirate ship, and the week after that Malayan rubber plantation. The late-1930s cars indicate this photo was taken some time around the early 1940s, but it could have been at time because they haven’t changed much. In the 1970s, that mountain in the background became Walton’s Mountain from TV’s “The Waltons,” and on the other side stands the Hollywood sign.