This is fill in the frame cause the picture is more focussed on the fire thing.   

before                                                                                              

after

The cropped photo illustrates the background rule of composition because it changes effect and it zooms into the picture .

 

                                         Ansel Adams 

      Ansel Easton Adams was an American photographer and environmentalist. His black-and-white landscape photographs of the American West, especially Yosemite National Park, have been widely reproduced on calendars, posters, and in books. 

http://www.biography.com/people/ansel-adams-9175697