HD Pentax-DA* 16-50mm F2.8 ED PLM AW

Conclusion

The DA* 16-50mm F2.8 PLM zoom lens is a worthy upgrade over its predecessor, and a welcome addition to Pentax's star lineup.

This lens replaces the original version first released in 2007. Users have a love-hate relationship with that lens, mainly because it is overly sensitive to aberrations and has a higher-than normal failure rate for the SDM motor.

In terms of autofocus speed, the new 16-50mm  is a huge step forward for Pentax. The lens is faster and quieter than anything else we have tested. Especially when coupled with the new K-3 III, the 16-50mm PLM is blazingly fast. This is done at a price: the lens uses a focus-by-wire mechanism, instead of the mechanical coupling found on almost every other lens from the company. Focus-by-wire is becoming the industry standard, especially for mirrorless, and thus it is not very surprising to see Pentax following suit. Given the excellent performance of the AF engine and the presence of quick-shift, this is not a true problem.  In addition, newer autofocus technology has shown to be significantly more reliable than Pentax's first-generation SDM, and the lack of mechanical components should further improve durability.

The new 16-50mm PLM is just as well-made as any other star lens: robust, solid, fully weather sealed and tightly assembled with a metal barrel. This lens is a workhorse and should reliably serve for many years.

The focal range is a classic. It offers great versatility. From landscapes to portraits, street photography and photojournalism, 16 to 50mm covers many use cases and applications.

Optically, the lens lives up to our expectations. Center sharpness is excellent at all apertures, except the narrowest. Edges and corners are not as good as the center, but can be used reliably.

Bokeh is gorgeous. The 9 curved aperture blades produce gradual transitions. Subject isolation is very effective. Highlights are well-shaped even as the aperture closes.

Distortion at medium and long focal lengths is well controlled. At the wide end it is more visible. This is not surprising but still something to be aware of.

Chromatic aberration and purple fringing are almost completely absent. These aberrations will not be a problem in everyday use. Sadly, the same cannot be said of flare. It is not the worst we have seen, but also not the best. Pentax lenses generally perform better.

Vignetting is one area where the lens exceeds our expectations. In most cases, even wide open, it is a non-issue.

Rendering is typical for a star lens, which is to say superb. Colors are rich but still neutral, there is a lot of detail in the shadows and transitions are pleasantly gradual. This lens is worthy of the star moniker, more so than its predecessor. Price and size are substantial, but for someone looking for a top performer, the 16-50mm PLM does not disappoint.

Pros

• Superb, rugged build quality
• Excellent center sharpness at all apertures
• Gorgeous bokeh
• Distortion almost absent at medium-long focal lengths
• Beautiful rendering with rich colors
• Among the fastest AF tested to date
• Low vignetting
• Better than average starbursts
• Well-controlled CA and PF

Cons

• Some flare present in most cases
• Softer corners at wider apertures
• Distortion at the wide end
• Bigger and heavier than its predecessor

Pricing

The DA* 16-50mm PLM commands a street price of $1396.95 as of Fall 2021. This is the same as the launch price from July 2021.

Rating

Ratings are format-specific. Handling will be influenced by the lens dimensions and weight, in particular for smaller APS-C camera bodies.

APS-C

Who Is It For?

As a "normal" zoom", the DA* 16-50mm F2.8 PLM is well suited for demanding photographers who want a fast aperture and reliable zoom for their APS-C camera. It is particularly well paired with the new Pentax K-3 III.

The focal range makes it a good general purpose lens, well adapted for low light photography. Its fast AF will be useful for fast moving subjects, such as concerts, photojournalism and even small children. 

Although it is not the only weather sealed lens with a convenient everyday zoom range, as a star lens the new 16-50mm also features dust protection, which may be desirable for outdoor photographers. 

However, users interested in compactness or something more affordable may instead prefer the DA 16-85mm F3.5-5.6.

The Bottom Line

With the HD DA* 16-50mm F2.8 PLM, Pentax continues to flesh out its "trinity" of F2.8 APS-C lens. Optically, it is better in all ways than the previous version it replaces. This lens is a worthy companion to the DA* 11-18mm F2.8 and the DA* 50-135mm F2.8 (the latter's optical capabilities are well-regarded, even though its AF is slow). The 16-50mm PLM is welcome addition to the K-mount lineup.

Be sure to check the user reviews or post your own if you already own this lens.