Mungo Ponton

Mungo Ponton FRS FRSE (20 November 1801 – 3 August 1880) was a Scottish inventor who in 1839 created a method of permanent photography based on potassium dichromate.

In 1815 he was apprenticed as a lawyer to James Balfour WS (of Pilrig House), working at chambers at 17 Broughton Street in the eastern New Town of Edinburgh.

In 1839, while experimenting with an early photographic process published that year by Henry Fox Talbot, Ponton discovered the light-sensitising effect of potassium dichromate.

Others experimented with his discovery, including Talbot, Edmond Becquerel, Alphonse Poitevin, and John Pouncey, some of whom patented their photographic techniques.

Ponton continued to work on photography and in 1845 the Society again awarded him a silver medal for his process for measuring the hourly variation in temperature on photographic paper.