A heartwarming video has emerged from the US of a 76-year-old grandfather's reaction to seeing colour for the first time after his relatives got him EnChroma glasses.<br /><br />The footage, shot in San Antonio, TX, on February 18, shows the joyful man when he discovers colours with the help of the special glasses. <br /><br />''My Father-In-Law is Red-Green Colourblind,'' the filmer later wrote online.<br /><br />''When we found EnChroma, the family wanted to give him the gift of colour.''<br /><br />''His reaction was priceless,'' he added.