Nikon NIKONOS Speedlight SB-103 Instruction Manual

Also see for Nikonos Speedlight SB-103: Instruction manual

PREPARATION-continued __-----'-- ___ _The preceding instructions must be performed on eachO-ring prior to each dive day and, if possible, prior toeach dive. By following these procedures and all otherprocedures in this instruction manual , you will be ableto enjoy using your Nikonos.8peedlight 8B-103 for manyyears.Reminder: An extra set of O-rings and a tube of lubri-cant are supplied with the flash unit. Additional O-ringsand lubricant are available from authorized Nikondealers and service centers.The O-rings and their sealing methodThe method used by the O-rings to seal and waterproofthe flash unit is shown in the following illustrations.When a low level of pressure exists (for instance, justunder the water 's surface), each O-ring seals its channelby its own elastic force (see Chart A). When the pressureincreases (at greater depths), the O-ring 's shape isaltered and its sealing ability is increased to withstandthe greater pressure. The pressure changes the ringfrom its original "0" shape (when looking at a cross-sectional view) to a "D " shape (see Chart B).Pressurei Jr-Chart A Chart Bo Slight compression60°"'"300 D-ring lubricant