SIGMA - Sigma 421DN17 Parts

Comprehensive technical documentation for the Sigma 421DN17 28mm F/1.8 Aspherical lens designed for Nikon AF digital SLR cameras. This document provides detailed technical drawings and a complete parts list for this professional-grade lens assembly. Page 1 features an exploded view diagram showcasing all major components, including the lens groups, focusing rings, and mounting elements in their proper arrangement. Page 3 presents an additional schematic representation illustrating the internal disposition and key functional components. The parts catalog identifies 11 main components with part numbers, English and Japanese designations, and quantities. Components listed include the lens hood (429M205), name rings, spacer elements, mounting screws, hood adapter ring, scale rubber ring, and the main focus barrel unit, along with critical subassemblies such as the 2nd group lens unit, cover ring unit, and focus barrel unit. Each part entry includes its reference number and precise identification. This documentation proves indispensable for maintenance technicians, optical repair specialists, and professionals seeking detailed knowledge of this lens system's construction and component specifications.