Though Lessley worked earlier with Roscoe "Fatty" Arbuckle, and later with Harry Langdon, he is best known for the groundbreaking effects he produced with Buster Keaton, who dubbed him "the human metronome" for his ability to crank consistently at any requested speed.

In The Playhouse, through use of a specially shuttered lens and repeated back-cranking and re-cranking, Lessley allowed Keaton to appear as up to nine characters simultaneously, interacting with one another.

[2] Shelton, a Confederate Army veteran, farmed and operated a general store with two sons from a previous marriage.

Filming was done entirely outdoors, including interior scenes which were shot on sets built outside and topped with cotton screens to control the sunlight.

[2] Lessley returned to Los Angeles, near his sister Nettie, and went to work for Mack Sennett at Keystone Studios.

His first screen credit is for The Waiters' Ball in 1916, but Lessley was seen (and photographed) working on He Did and He Didn't with Roscoe Arbuckle and Mabel Normand in late 1915.

Roscoe Arbuckle ... was superintending the construction of a set, aided by Ferris Hartman, his co-worker, and a dozen prop men; Elgin Lessley, the intrepid camera man, who has the reputation of turning out the clearest films of any Keystone crank turner, was loading his magazines.

[7] The rough and tumble atmosphere on an Arbuckle shoot[7] likely went far in preparing Lessley for his later work with Buster Keaton, who had standing orders for his cameramen to keep filming his risky stunts no matter what, until he either yelled "Cut" or was killed.

He shot a number of movies starring Arbuckle's nephew, Al St. John, including A Self-Made Hero,[8] The Stone Age,[9] and A Winning Loser.

[11] Arbuckle had already recruited Buster Keaton, and when Lessley came aboard Comique in 1918, he began their working relationship with The Bell Boy.

When filming The Playhouse in 1921, Keaton was recovering from a broken ankle, and thus was unable to perform his usual death-defying and physically punishing stunts.