Hi Dennis and thanks for your comment.
The difference between fireworks in Chantilly and others fireworks is due to the fact that Chantilly is a competition between fireworks producers ! They all have the same budget for their show, but this budget allow them to fire hundreds of shells so the result is different.
I used my tripod, I also shoot on iso 200, but at f/8, and of course with shutter on bulb. After it's more a question of chance and practice to determine the lenght of the shutter time.
As indicated below the pictures, I shot these pictures with my Canon EOS 33.
Patrick