Felice Beato's Flash Powder

Origin
Felice Beato was an Italian-British photographer who traveled extensively through the Mediterranean and East Asia as one of the first war photographers. His works captured events foreign and remote to most westerners, including the Indian Rebellion of 1857 and the Second Opium War.

Effects
After absorbing the horrors of war, the powder allows the user to capture any moment they have lived on film. To activate, the user must only sprinkle the powder onto a piece of paper, and the image from their memory will appear in photographic quality.