Captain Captain Augustus Frederick Keppel, 5th Earl of Albemarle Viscount Bury
Bury was commissioned an ensign in the 1st Regiment of Foot Guards on 7 April 1811. He was promoted to Lieutenant and Captain on 12 January 1814. In 1815, he was appointed aide-de-camp to William, Prince of Orange and fought at the battle of Waterloo.
Uniform:
In my opinion this site is the best source of uniform reference for the 100 days (Waterloo) campaign: