What a marvelous experience that must have been!
I am surprised that they use 2" eyepieces though. I would have thought larger format eyepieces would have been better suited, and these can have longer focal length too.
All the same, to look into the core of a GC, and see colour in individual stars, magic!
I'd love to have some time with that scope with a sketch pad in hand, despite the narrow field of view.
Alex.