INON D-180 ManualVersion 1. October 4, 2003Copyright 2002, 2003 by INON America, Inc. All rights reserved.14subject reflectivity measured TTL; based on this information, second (main) flash duration iscalculated, and then strobe fires main flash quickly afterwards, only for the specified duration.(Pre-flash TTL Auto Exposure Adjustment)3) During exposure, strobe itself measures in real timez Using a light sensor in the strobe, subject reflectivity measured in real time, with strobequenching at time of “proper” exposure. (External Auto Flash Exposure Adjustment)For each of these automatic flash adjustment methods to work, besides a signal instructing theexternal strobe to fire, the various combinations of cameras (and master strobes) and externalstrobes must be compatible with each other’s signal transmission methods.- In case of 1) above: From Camera to External Strobe Instruction to stop flash- In case of 2) above: From Camera to External Strobe Instruction to stop flash; or,Instruction for flash durationExternal Strobe to Camera External strobe information- In case of 3) above: From Camera to External Strobe ISO Sensitivity information, andAperture Value informationAs of December 2002, a majority of consumer digital cameras use Pre-Flash TTL Auto ExposureAdjustment. Unlike conventional 35mm film camera systems with the widely adopted Real TimeTTL Auto Flash Adjustment, most current digicams cannot use such automatic exposureadjustment with external strobes. Likewise, except for some dedicated land strobes for certaincamera brands, there are no external strobes yet available fully compatible of functioning with thevarious Pre-Flash TTL Auto Exposure Adjustment type cameras available. The main reasons are:z Because pre-flash specifications and protocol have not been standardized between the cameramanufacturers.z The external strobe to camera signal transmission specifications have not been standardizedbetween camera manufacturers, and the communication method used by most existing externalstrobes has not been adopted in most digital cameras.Due to the lack of real time information from camera to strobe, digital cameras cannotautomatically adjust exposure with external strobes. Therefore it is necessary for the externalstrobe itself, to a certain extent, independently execute automatic flash adjustment.The D-180, as an External Auto Flash Exposure Adjustment type of strobe, and using an AdvancedCancel Circuit, is compatible with the vast majority of digital cameras using Pre-Flash TTL AutoExposure Adjustment, and of course Real Time Auto Exposure Adjustment type cameras.Regardless of the camera type, automatic light adjustment is possible with the D-180 external