Semler was born in Renmark, South Australia. His first work in the production industry was as a camera operator at a local television station. Later, he began making documentary and educational films for Film Australia. He was the cinematographer for A Steam Train Passes (1974), Moving On (1974), Let the Balloon Go (1976), and A Good Thing Going (1978).
1980s
His first film was Stepping Out, in 1980. Allmovie praised his "stunning work" on the film Hoodwink (1981) with a screen play by Ken Quinnell. Semler was also the cinematographer for Mad Max 2 (1981). Semler's vast panoramic shots of the Australian Outback's deserts "...convincingly conveyed a parched, dusty, post-apocalyptic world"[5] and led to international attention for his work. Semler also acted as cinematographer for the follow-up film to The Road Warrior, Mad Max Beyond Thunderdome (1985). Semler was also a cinematographer for the acclaimed Australian miniseries Bodyline (1984).[6] In the late 1980s, Semler was the cinematographer for several popular films, such as Cocktail (1988) and Young Guns (1988).
In the 2000s, Semler was the cinematographer for a range of movies that included comedies (Nutty Professor II: The Klumps from 2000, and Bruce Almighty from 2003), action films (XXX from 2002 and The Alamo from 2004). In the mid-2000s, Semler was the cinematographer for the football comedy The Longest Yard (2005) and Just My Luck (2006). In 2006, Semler worked with Mel Gibson again for the film Apocalypto. Semler's camera work conveyed the beauty of the lush Mesoamerican jungle setting in Apocalypto.
