The DA* 16âÂÂ50mm lens is a family of professional wide-angle lenses made by Ricoh Imaging. The current version, the HD DA* 16-50mm f/2.8L ED PLM AW, replaced the older smc DA* 16-50mm f/2.8 ED IF SDM lens in 2021.
The Pentax smc DA* 16-50mm F2.8 ED AL (IF) SDM was an advanced standard zoom lens for Pentax K-mount APS-C DSLR bodies, announced by Pentax on February 21, 2007. The lens suffered from frequent failures of the SDM autofocus drive motor due to design flaws. It also received poor reviews due to sub-par optical performance for a lens with the professional star rating. The lens was discontinued in late 2023.
The Pentax HD DA* 16-50mm F2.8 ED PLM AW is a professional standard zoom lens for Pentax K-mount APS-C DSLR bodies. Development was announced on 25th May 2020, officially product name announced on October 25, 2021, launched on July 15, 2021 and first shipped in August 2021. As a replacement for the poorly regarded earlier version, it featured a new pulse linear motor (PLM) focusing motor design and refined optical structure, largely alleviating issues with the prior version. As a result of these changes the lens gained 147 grams and 18.5mm in length over its predecessor.