[MartinMcFly]

I have used the DA18-135WR on my K7 for the last 2 years and love it. It's now on my new K5ii and still impressing me. A slightly wider aperture would be nice but then it would make for a bigger lens and wouldn't be so versatile. To be honest it hardly ever leaves my camera, I'm not a pro photographer or a pixel peeper. I just love the fact that it's a great all round lens, quiet and fast AF and when it gets a bit (or a lot) wet I don't have to pack up my gear.

[Clavius]

I normally prefer to use my primes, but the 18-135 is my only WR lens, and living in the Netherlands (where it rains 80% of the time) means that the WR lens gets to see lots of action. I love it, for a superzoom it has very decent IQ imho.

[clawhammer]

I don't like hearing this kind of thing. It makes me paranoid about my lenses. None of mine are grossly out of whack, but my fear is that they are a little off and I just can't tell. I like to think that spending hundreds of dollars on a lens will almost guarantee me quality optics.

It amazes me how often we get paralyzed like this; it must say something about the human psyche that everything has to be 100% perfect. I used to fret and worry about whether my stuff was working perfectly, but then I had an epiphany: If I can't see it in my photos, then who cares if it doesn't shoot a test chart as good as another copy? I didn't buy it to take pictures of test charts, I bought it to have fun with.

tl;dr: if it looks fine, stop worrying and enjoy photography.

[lytrytyr]

Congratulations. I just wish some reviewers had done the same.......

"Just to mention again -
we couldn't believe the rather poor performance
so we asked the local Pentax service
in Hamburg/Germany for an assessment of the situation.
Result: the lens is within factory specifications."

From

Pentax SMC-DA 18-135mm f/3.5-5.6 ED AL [IF] WR - Review / Lens Test - Sample Images & Verdict