REMOVE

1. buildings (structures)
2. hats
3. utility poles
4. platforms (general)

WHAT

1. Visual Works (hierarchy n … (1)
2. artists (visual artists) (1)
3. beaches (1)
4. black-and-white film (1)

More 

WHERE

1. Ensenada, Baja California … (1)

WHEN

1. 1949 (1)
2. circa 1949 (1)