I bought this lens as my one and only bad-weather zoom. Physically it is about the same size as my 18-250mm Pentax superzoom, but for what it loses (100mm plus of zoom at the long end), it makes up in the comfort of knowing it's weather-sealed, and I can face light drizzle with confidence and downpours with the knowledge that if I get inside soon enough, my camera and lens will not be destroyed or shorted out. Thus far I am quite happy with it - it offers enough focal length "span" for the tasks I bought it for (wide enough at the wide end; tele enough at the other), and more than adequate image quality.
Handling is good, and manual focus override is quite reasonable with "quick shift" - the MF ring is nicely damped, making manual adjustment easy, or if you're moving from near to far objects (or vice versa) you can give the focus ring a twist and let the AF do the rest of the work. The inbuilt DC motor doesn't seem notably faster than screw-drive, but it is accurate when lighting is adequate (see below) and is generally much quieter where this is important. The lens is advertised as being incompatible with some older digital bodies (all *ist-D... series, K100D, K110D) as they do not support the inbuilt autofocus motor, so take care if you are buying a cheap body and this lens separately second-hand.
The only problem I have had with it is I've had trouble locking focus sometimes. However, this has always occurred in quite low-light situations, where variable-aperture zooms like this one aren't at their best without strong focus-assist from an external flash (which I don't have). It really can't really be put down to the lens, which I seem to be pushing to its limits in low light on the K-5.
If you can only have only one lens on your Pentax DSLR, this is a good choice, especially if you are travelling to wet and/or dusty places and don't want to fiddle with lens changes much. It doesn't give quite the range that the 18-270 does or quite the image quality that some of the other higher-end lenses do, but the weather sealing makes it an excellent practical choice, and if you use it well it will give you excellent results for amateur or enthusiast work. Especially if you're just getting into DSLR, this lens as part of a lens-body deal is an excellent option and will keep you going for quite a while before you need to consider anything else.
| Manufacturer | Pentax |
|---|---|
| Place of Business | Mississauga, ON L4W 5M3, CA |
| Item model number | 21977 |
| Product Dimensions | 7.6 x 7.3 x 7.3 cm; 405 g |
| ASIN | B0043RTLA6 |
