Designed for use in both rainy and dusty conditions the Pentax 16-50mm f/2.8 ED AL (IF) SDM features weather-resistant and dust-resistant seals for enhanced durability. There are no full-frame models in the Pentax D-SLR line-up so the 16-50mm f/2.8 ED AL (IF) SDM is compatible with all Pentax models. In keeping with high-end D-SLRs in Pentax’s range, like the K-7, it features a weather-sealed construction for enhanced durability and there’s also a large and smooth manual focus ring, as well as Quick Shift Focus that allows you to focus manually in AF mode.
This lens boasts a Supersonic Drive Motor for quick, quiet autofocus and although not the fastest ever, it performed well, with minimal hunting. The zoom ring on our sample wasn’t quite as good though, as we found it a tad stiff in the middle of the range.
Optically it features an aspherical and an ED element, together with lens coatings to improve image quality and minimise smears. The supplied hood has a window for rotating circular polarisers, and Internal Focusing ensures the front element doesn’t rotate as the lens focuses.
You can use the AF/MF switch to set the focusing mode, but the Pentax Quick Shift Focus system allows you to focus manually while still in AF mode.
www.pentax.co.uk