Thanks to its seven rounded aperture blades, the 18-270mm has surprisingly good bokeh for a consumer zoom lens. Even though it lacks a true macro mode, its longer focal lengths will let you get pleasing bokeh even when stopped down. We'll let the images speak for themselves in this section.
Images of cactus needles can be difficult for zoom lenses to render because zooms generally do not produce a smooth out of focus area. The bokeh isn't quite on par with that of a fast prime, but we've seen much worse and we'd say that the 18-270mm handled this shot fairly well!
270mm @ F9.5: Click image to enlarge | Download full-size image
The next shot was taken at F5.6 at 115mm, so basically with the lens fully open.
The new Pentax 18-270mm has above-average bokeh which is comparable to that of the 18-135mm WR. We have no complaints and believe that bokeh is one of the 18-270mm's strongest points when it comes to image quality.