It Might Just Be An Actual Candid

Most "candids" of stars taken by the studios were staged more than a still taken on the set.  In the photo below, it appears Bob is standing outside of a studio building, perhaps on a break, reading a script or newspaper or racing sheet.  With the trash can as part of the background and the look on Bob's face, I would guess it is an actual candid.  Unless...perhaps Bob, the avid photographer, has set it up, having someone take the photo for him, wanting to show his work environment behind all the glamour.  It is difficult to distinguish what is reality from the image Hollywood portrayed of itself. 

I am guessing, primarily because of the hat, that Bob is filming Live, Love and Learn (1937).  Yes, a lot of guesswork is involved in trying to identify just what is happening in photos taken 80 years ago.