REMOVE

1. rock
2. workers
3. sky
4. garages
5. boys
6. bushes

WHAT

1. black-and-white film (1)
2. branches (plant component … (1)
3. exterior views (1)
4. freight cars (1)
5. houses (1)
6. ladders (1)
7. plants (1)
8. railroads (1)
9. rails (transit system ele … (1)
10. roads (1)
11. scaffolds (1)
12. signs (declatory or adver … (1)
13. soil (1)
14. trains (vehicle groupings … (1)
15. trees (1)
16. Visual Works (hierarchy n … (1)
17. wheels (components) (1)
18. windows (1)
19. wrecks (sites) (1)

WHERE

1. New Windsor, Maryland (1)

WHO

1. Campbell, Sandra L. Still (1)
2. Clyfford Still; Still, Cl … (1)
3. Sandra L. Still Campbell; … (1)
4. Still, Clyfford (1)

More 

WHEN

1. 1969 (1)