The smc PENTAX DA* 55mm is more than equal to its analogue predecessor: tremendous light gathering capabilities, circular diaphragm for outstanding bokeh and a fine progressive rate of sharpness depth. Additionally, the lens features a newly developed PENTAX lens coating that further reduces light loss and reflections. For the professional portrait photographer this lens is undoubtedly the finest on the market. It is developed exclusively for the use with SDM compatible cameras.

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smc DA* 55mm f/1.4's lens mount is KAF3-type, which means that with K100D, *ist D, *ist DS, and *ist DL, the focus can only be performed manually.