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Jim King | profile | all galleries >> Galleries >> PENTAX FA50/1.4 VS. DA*55/1.4 Lenses - Bokeh Comparison tree view | thumbnails | slideshow

PENTAX FA50/1.4 VS. DA*55/1.4 Lenses - Bokeh Comparison

These images compare the out-of-focus blur, or bokeh, of these two lenses. The first subject is an artificial flower arrangement in the center of a table about 2 meters from the camera. It is flanked by two candlesticks, one about 1/3 meter in front of the arragement and one about 1/3 meter behind the arrangement. As I focused on the flower arrangement both of the candlesticks are slightly out of focus. I took two shots with each lens, one wide open at f1.4 and the other closed 2 stops at f2.8.

The second set of images is of the highlight reflections from a brass chandelier about 2 meters from the camera. Both lenses are focused at their minimum focusing distance of 0.45 meter, so the highlights are deliberately very much out of focus. Again, I took two shots with each lens, one wide open at f1.4 and the other closed 2 stops at f2.8. This "highlight bokeh" is often quite different than the "object bokeh" of the first series.

Both lenses were mounted on my Pentax K20D DSLR positioned on a tripod under incandescent light. No post-processing was done other than image size reduction and modest JPEG compression.

While I don't see much difference in the bokeh of the two lenses in the first series (the biggest difference is the amount of blur due to the difference in focal length), I find that the bokeh in the second series is somewhat better (to my eyes) with the DA*50/1.4 lens, especially at f2.8. This is probably due to the larger number of aperture blades in the DA*55/1.4, which creates a rounder aperture in the lens, and thus a rounder border on the OOF circles.

Bokeh is a subjective image property and opinions about whether it is pleasing or not differ between observers.
IMHP1944 FA50@1.4.jpg
IMHP1944 FA50@1.4.jpg
IMHP1945 FA50@2.8.jpg
IMHP1945 FA50@2.8.jpg
IMHP1946 DA*55@1.4.jpg
IMHP1946 DA*55@1.4.jpg
IMHP1947 DA*55@2.8.jpg
IMHP1947 DA*55@2.8.jpg
IMHP1948 FA50@1.4.jpg
IMHP1948 FA50@1.4.jpg
IMHP1949 FA50@2.8.jpg
IMHP1949 FA50@2.8.jpg
IMHP1950 DA*55@1.4.jpg
IMHP1950 DA*55@1.4.jpg
IMHP1951 DA*55@2.8.jpg
IMHP1951 DA*55@2.8.jpg