Jack was art director and member of the original Amiga computer design team from 1984 to 1986. He was the first artist (together with Sheryl Knowles) to create graphics with the Amiga computer.
Some images were created with such early prototypes that it wasn't possible to save them to disk. Instead Jack had to make screenshot by taking photos of the actual monitor with a 35mm camera.
In an interview that he did for the first issue of Amiga World Magazine he stated
Up to this point, a lot of computer graphics has been qualified as good simply because it was done on a computer, but that isn't enough. In my mind, it must first stand on it's own as graphic art and secondarily as work done on a computer. You can't just be in love with the media for its own sake. The images must fulfill the fundamental criteria of good design and aesthetics. A sense of humor is also important. I think that the computer is an extremely dynamic tool for creating and manipulating graphic art, and the impact that the computer will have on the graphic world is going to be tremendous.