A Chan (YA Zhen) was a Chinese photographer and dentist, with a studio in Guangzhou (Canton) and in Hong Kong. UB01-20 shows the sign outside the Guangzhou (Canton) studio/shop. A Chan (Ya Zhen) specialised in local Canton views. A Chan’s photographs were often printed with a caption, characteristically in capital letters, in white, placed near the lower margin of the print. Source: Terry Bennett History of Photography in China - Chinese Photographers - 1844-1879, Quaritch 2013, pp118-121.