Braff ran a crowd-funding Kickstarter campaign for the film, raising more than $2 million in four days.
Braff will direct and star in the film, which is based on an original screenplay he wrote with his brother, Adam Braff.
In "Wish I Was Here," Braff plays Aidan Bloom, a struggling actor, husband and father, who is searching for his purpose for life. As he and his wife try to make ends meet, he fantasizes about being the great futuristic Space-Knight he dreamed of as a child.
Patinkin's feature film credits include " Yentl," "The Princess Bride," "Everybody’s Hero," "Pinero," "Lulu On The Bridge," " Ragtime" and "Dick Tracy." Some of his Broadway credits include Evita, Sunday in the Park With George, The Secret Garden, The Wild Party and An Evening with Patti LuPone and Mandy Patinkin.