I'm running a Haunted House exhibit at my school to raise money, and I had the idea of taking pictures of the "victims"/students remotely with my Sony DSLR camera and then printing and selling the photos as the students exit the haunted House (much like amusement parks do with roller coasters as you go down the final drop, or when one takes pictures with Santa Claus at the mall). Does anyone know of any free/relatively inexpensive software that would allow me to do this? I would prefer Mac-compatibility, but it's not a requirement.