Pentax DA 20-40mm f/2.8-4 ED Limited DC WR Lens Silver

I have a K5IIs and had been using the surprisingly competent 18-55 WR lens (current version). The 18-55 WR lens yields very sharp and crisp images in the center, but not on the margins. So, I thought I'd try the 20-40 as an alternative (I use my little Pentax as an alternative grab-n-go camera to my other grab-n-go camera, my Leica M240). What results I'd say conservatively that the 20-40 is an order of magnitude sharper in the center and along the margins, very sharp, compared to the 18-55 WR. Normally I shoot with a Leica S006 or M240 and frankly this little lens, while certainly not Leica S or even Leica M equivalent, produces very sharp and acceptable images at a fraction of the cost. I've found the 20-40 to produce sharp and crisp images at all focal lengths. ... MoreI have a K5IIs and had been using the surprisingly competent 18-55 WR lens (current version). The 18-55 WR lens yields very sharp and crisp images in the center, but not on the margins. So, I thought I'd try the 20-40 as an alternative (I use my little Pentax as an alternative grab-n-go camera to my other grab-n-go camera, my Leica M240). What results I'd say conservatively that the 20-40 is an order of magnitude sharper in the center and along the margins, very sharp, compared to the 18-55 WR. Normally I shoot with a Leica S006 or M240 and frankly this little lens, while certainly not Leica S or even Leica M equivalent, produces very sharp and acceptable images at a fraction of the cost. I've found the 20-40 to produce sharp and crisp images at all focal lengths. However, I've shot mostly between 30-40 and at f9. As noted, excellent sharpness. I've also shot at the maximum apertures and the out of focus areas are generally smooth and pleasing to look at (not Noctilux Bokeh but very acceptable). To sum up my experience I've been very pleased with the sharpness across the lens, the auto focus has been accurate and reasonably fast (the K5IIs is not an auto focus champ to begin with) and much more enjoyable with the new DC motor vs. the old screw-type. Finally, the images have been well saturated and contrasty, and with very little trace of CA or excessive distortion (shooting in RAWJPGs will have near zero distortion due to in-camera corrections). If you don't mind spending a little above average for a relatively narrow focal range zoom, this little Pentax 20-40 will be very rewarding to you.

Lats year I purchased a KF and the DFA 28-105 which is a decent lens but not very wide on a crop camera. Decided to go with the 20-40 Limited mainly to get a wide-angle option. Zoom range seemed a bit odd at first but is proving to be very practical the more I use it.Have been VERY pleased with image results from 20-40 LTD. 90% of the time I am shooting at f5.6 or f8 and the lens is sharp all around. If you are getting your first DSLR I would highly recommend the Pentax KF with the 20-40mm Limited as a starting point/kit. Very nice lens.

This lens is a pleasure to use and takes very high quality pictures. As someone else told me, it is like having 2 prime lenses (20 and 40 mm) in one housing. The only problem I had was I initially purchased a 55 mm Tiffen UV filter to protect the lens. BIG mistake. As I learned the hard way, never put a cheap UV filter on an expensive lens. It degrades resolution. I replaced the junk Tiffen with a B+W UV Haze filter and image quality is excellent. See the photo for a crop of images taken at F/2.8 and 20 mm focal length, with No filter and a B+W UV-Haze filter. I can not see any difference. While the Tiffen image (not shown here) was badly degraded.