Complex sentence: Radcliffe was initially meant to wear green contact lenses as his eyes are blue, and not green like Harry's, but the lenses gave Radcliffe extreme irritation, and, upon consultation with Rowling, it was agreed that Harry could have blue eyes.
Split into simpler sentences: Radcliffe was initially meant to wear green contact lenses as his eyes are blue, and not green like Harry's, but the lenses gave Radcliffe extreme irritation. Upon consultation with Rowling, it was agreed that Harry could have blue eyes.