Several of Armitage's subjects stand out from the company's regular routine of actualities and comic skits in their innovative use of camerawork, superimpositions, time-lapse photography and other effects then new to the art of film-making.
Several of the actualities Armitage filmed that year had to do with the end of the Spanish–American War, including views of the battleships which fought in it and the welcome home parade thrown for Admiral Dewey in New York City.
On June 9, 1899, Armitage was one of three Biograph cameramen to photograph the heavyweight championship bout between Jim Jeffries and Tom Sharkey, the finished film running a then-record time of 135 minutes.
Armitage deliberately projected part of the negative in The Ghost Train (1901) and used time lapse photography—taken over a period of a month—in Demolishing and Building Up The Star Theater (1901).
Even a basic understanding of Frederick S. Armitage's contribution to film didn't get underway until the 1980s, with the work of Charles Musser, and a lot remains to be known about what he did and who he was.