I searched a host of Brown Derby posts, fwiw, but didn't see this one.
It's unusual in that it's of the Wilshire location, but is taken from the opposite side, the coffee shop annex, where you don't see the "derby" shaped hat.
The Chapman Park Hotel sign is visible across the street next to what make of automobile?
For comparison, here's another photo taken from the opposite direction.
Both photos were just marked c. 1950's.
What is that large box-like thing for on the roof?
Love the lady's colorful coat and the man hosing off the street.
(Oh, the good old days when people had water for such things!)