Yesterday, I posted photos showing that the semi-wide SMCP K 35mm f/3.5 can be coaxed to produce decent bokeh although it was never designed for it (see here
How to Coax a Wide Angle Lens to Render Pleasant Bokehs). In fact, reviews in this forum gave it an average of 7.3 for bokeh, which is way below the ratings for the other attributes. That is not surprising given that wide-angle lenses are not optimized for bokeh. However, this
35mm lens can produce decent bokeh provided two conditions are met: lighting is soft/diffused and subject is placed at minimum focusing distance. I also discovered that this lens gives adequate DOF necessary for flower shots. I've always struggled finding enough DOF using my 50mm and 100mm macros even at f/22. I've always wanted a DOF that would cover the pollen-laden anthers at the tip of the filaments down to the lower portions of the pistil.
I decided to take my discovery to the next level. I went to the same park again earlier. The lighting condition was nearly the same as yesterday's at this time of the day. I mated the lens to an Asahi Pentax auto extension tube (No. 1; length = 12mm). Below are the photos at different apertures at f/3.5, f/4.0, f/5.6 ... up to f/22.0. These are jpeg files straight out of my
K5 and completely unretouched but resized.
My conclusions? Combined with 12mm-long extension tube, the SMCP K 35mm f/3.5 lens (1) is a viable alternative for getting "semi-macro" shots; (2) yields adequate DOF especially for flower and similar shots; (3) produces wonderful bokeh from f/3.5 to f/8.0 (the background becomes too busy for my taste starting at f/11.0); and (4) can be a creative tool in producing "artsy" shots not normally associated with wide angles. And here are the other pluses: the sharpness and the classic Pentax contrast of this lens are amazing. The only drawback is the need for a tripod when using low ISO.
Last edited by chmance; 06-28-2015 at 08:35 PM.
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