A facsimile of the essays as they appeared in Penrose's Pictorial Annual Written by Upendrakishore Raychowdhury The exponential growth of high-detail photographic reproduction over the last century is premised on the minute half-tone dot, which is also the forebearer of the contemporary digital pixel. Upendrakishore Raychowdhury was an internationally recognized pioneer in the field and is credited with inventing one of the key components of the half-tone process. Between 1897 and 1912, he wrote nine essays on aspects of his half-tone technique for Penrose's Pictorial Annual, a London-based periodical of the graphic arts. This edition brings together the essays for the first time, and in facsimile. Publication Jadavpur University Press