SDM definitions

SDM

Silent Drive Motor. An autofocus mechanism (Pentax brand).
Found on http://en.wikipedia.org/wiki/List_of_abbreviations_in_photography

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SDM

System Development Multitasking
Found on http://www.encyclo.co.uk/visitor-contributions.php

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SDM

Sensing and Diagnostic Module
Found on http://www3.sympatico.ca/dhaughey/j1930.htm

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