I would highly recommend CSW Film Systems on 215 N. Damen, Chicago, (312) 226-7810. I don't know if they do chemical prints from transparencies. They do C-prints from negatives and are great at getting colors just right. Oson who owns and operates CSW is one of the best color correctors in the city. THey process E-6 and C-41 in all sizes at least up to 4x5.