The smc Pentax-F 17-28/3.5-4.5 Fisheye Zoom is unique! No other manufacturer has anything like it.
At 17 mm it covers 180 degrees diagonally (on a 35mm camera, somewhat less on the *istD). It may not be the sharpest game in town, but it is fun to use.

This autofocus lens weighs just 255 grams, has 9 optical elements and a built-in lens hood. Being this compact you tend to carry it with you at all times. It does not take any filters.

This gallery shows various photos taken with the Pentax *istD and this lens.

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