One of his photos at the exhibition shows the side profile of an aged ferryman on the Yellow River, which Zhu says reminds him of his father, "a kind and industrious man".

"When I left home, my father said to me, 'Don't break the law; don't cheat others'," he explains.

"I'm not an artist, but a faithful reporter of time and history.

"I will keep working as long as I can walk. I want to leave something through which the younger generations will learn about the changes our nation has undergone."