In 1991 four men in two balloons achieved the first hot-air balloon flight over Mount Everest. In one balloon was Andy Elson and Eric Jones (cameraman), and in the other balloon Chris Dewhirst and Leo Dickinson (cameraman). Dickinson went on to write a book about the adventure called Ballooning Over Everest. The hot-air balloons were modified to function at up to 40,000 feet altitude. Reinhold Messner called one of Dickinson's panoramic views of Everest, captured on the now discontinued Kodak Kodachrome film, the best snap on Earth, according to UK newspaper The Telegraph. Dewhirst has offered to take passengers on a repeat of this feat for US$2.6 million per passenger.