Question: Were both Ted Tetzlaff and David Siegel film actors?

Context paragraphs:
Ted Tetzlaff: Dale H. "Ted" Tetzlaff (3 June 1903, Los Angeles, California – 7 January 1995, Sausalito, California) was a noted Academy Award-nominated Hollywood cinematographer active in the 1930s and 1940s.

The Window (film): The Window is a 1949 American black-and-white suspense film noir, based on the short story "The Boy Cried Murder" (reprinted as "Fire Escape") by Cornell Woolrich about a lying boy who suspects that his neighbors are killers.  The film, which was a critical success, was produced by Frederic Ullman, Jr. for $210,000 but earned much more, making it a box office hit for RKO Pictures.  The film was directed by Ted Tetzlaff, who worked as a cinematographer on over 100 films, including another successful suspense film, Alfred Hitchcock's "Notorious" (1946).  For his performance in this film, Bobby Driscoll was presented with a miniature Oscar statuette as the outstanding juvenile actor of 1949 at the 1950 Academy Awards ceremony.

Johnny Allegro: Johnny Allegro is a black and white 1949 American film noir, starring George Raft, Nina Foch, Will Geer, and George Macready.  An ex-gangster (Raft) working as a federal agent runs afoul of a crime lord (Macready) who enjoys hunting humans for sport.  The picture was directed by Ted Tetzlaff and produced by Columbia Pictures.

Riffraff (1947 film): Riff-Raff is a 1947 black-and-white film starring Pat O'Brien, Anne Jeffreys and Walter Slezak.  Considered a minor film noir entry more in the adventure genre, it was directed by Ted Tetzlaff, who also directed "The Window" (1949) and worked as a cinematographer for over 100 films, including another successful suspense film, Alfred Hitchcock's "Notorious" (1946).  The music was composed by Roy Webb and Joan Whitney.

The Young Land: The Young Land is a 1959 American Western drama film directed by Ted Tetzlaff starring Patrick Wayne and Dennis Hopper.  The cinematography was by Technicolor developer Winton C. Hoch and Henry Sharp.  The film was distributed by Columbia Pictures Corporation.

Time Bomb (1953 film): Time Bomb is a 1953 British-made MGM post-war thriller film written by Kem Bennett and directed by Ted Tetzlaff.  It starred Glenn Ford and Anne Vernon.  In the US it was released under the title Terror on a Train.

Son of Sinbad: Son of Sinbad is a 1955 American film directed by Ted Tetzlaff.  The movie takes place in the Middle East and consists of a wide variety of characters including over 127 women.

World Premiere (film): World Premiere is a 1941 American comedy film directed by Ted Tetzlaff and written by Earl Felton.  The film stars John Barrymore, Frances Farmer, Eugene Pallette, Virginia Dale, Ricardo Cortez, Sig Ruman and Don Castle.  The film was released on August 21, 1941, by Paramount Pictures.

Fighting Father Dunne: Fighting Father Dunne is a 1948 American biographical film about the life of Father Peter Dunne, and the creation of his News Boys Home in St. Louis, Missouri.  Directed by Ted Tetzlaff, the screenplay was written by Martin Rackin and Frank Davis, based on an original story by William Rankin.  The film stars Pat O'Brien as Fr.  Dunne, along with Darryl Hickman, Charles Kemper, Una O'Connor, Arthur Shields, Harry Shannon, Joe Sawyer, Myrna Dell, and Ruth Donnelly.

David Siegel (screenwriter): David Siegel is an American film director, screenwriter and producer, and part of a long-standing writing-directing-producing team with filmmaker Scott McGehee.

Supporting paragraphs: Ted Tetzlaff David Siegel (screenwriter)
Answer: no