(written from a Production point of view)
Markel studied at Michigan State University and later transferred to Vancouver Film School, where he created a short film called The Levis HVC. This project was screened in SIGGRAPH's Electronic Theater as part of conference's Computer Animation Festival in 2002. 
Markel's professional career in previsualization began in 2002 when he joined Lucasfilm and was assigned to George Lucas' director's cut edition of THX 1138. Markel and his six fellow previsualization artists from this project became the founding members of The Third Floor. Markel and his fellow Third Floor founders later designed shots for the 2005 film Star Wars: Episode III - Revenge of the Sith, after which Markel became a previsualization artist on the 2005 remake of War of the Worlds, apart from The Third Floor.
In 2005, Markel traveled to Australia to lead the previsualization work for the 2007 film Ghost Rider (featuring Brett Cullen). Since returning to the United States, Markel has worked as part of The Third Floor on such films as Evan Almighty (featuring Jimmy Bennett, Gregg Daniel, Bruce Gray, William Dennis Hunt, Harve Presnell, Tucker Smallwood, and Ruth Williamson) and Cloverfield (produced by J.J. Abrams and featuring Margot Farley, Scott Lawrence, Pavel Lychnikoff, and Kelvin Yu).