Afterwards, he attended the Joe Kubert School of Cartoon and Graphic Art in Dover, New Jersey from which he graduated in 1989.
Tinsley began working for Marvel Comics in 1990, initially doing art corrections as one of Romita’s Raiders, before moving into the production department, colloquially known as the Bullpen.
Between 1994 and 1996, Marvel made a transition from all analogue hand-pasted mechanicals to a company-wide digital workflow.
The sales of this book provided the financial foundation on which Tinsley began publishing his own first-run graphic novels, including The Festering Season and the Stonehaven series.
In December 2001, Marvel Comics asked all colorists to submit bids for coloring work so that it could lower its production costs, leading Tinsley to sever his freelance ties with the company.