The link below will take you to a short film of the 1983 scoring session for SOMETHING WICKED THIS WAY COMES, conducted by a very young James Horner. Horner was only about 30 years old at the time of this event. Tragically, Mr. Horner, an avid pilot, would later die in a 2015 plane crash at the much too young age of 61. Ray Bradbury himself attended the scoring session, and can be seen starting at about seven minutes and fifteen seconds into the film:

https://www.youtube.com/watch?v=uuifKU2NNfU