I found some 'DUFAYCOLOR' mounted sldes in a box , taken about 1953 on my 'Ensign Selfix 16/20 Model II'. It was an 'Additive Process' - a silver image was viewed through a coloured 'Reseau' of Red, Green and Blue lines
As grahamp states on another print -these were taken just 13 years after Dunkirk. It looks like there are a couple of WW2 MGB/MTB's moored up on the harbour wall.
Anyway - lovely images, thanks