Optically, we can’t find a whole lot to complain about with the Pentax 17-70mm ƒ/4. It’s decently sharp even wide open; light falloff and distortion aren’t much to be concerned about. Outside of the middle of the zoom range, the numbers for chromatic aberration are a little high for our taste: I’d assume that in order to keep costs down, Pentax opted not to include ED glass elements. However, the cost is already at the $600 level, which makes it sort of a loss-leader to the Pentax 16-50mm ƒ/2.8, which can be had for as little as $700, and offers pro-level performance at the cost of a little telephoto distance.

Pentax 17-70mm f/4 DA SMC AL IF SDM Lens for Pentax Digital SLR Cameras

Overall Rating:

Retail Price: $599.95

Amazon Price: Too low to display

In the meantime, the Sigma and Tamron alternatives are strong contenders, offering similar (if not better, in the case of the Tamron) performance for significantly less money. But for Pentax purists who want to stay loyal to the brand, and want a better-performing kit lens than the 18-55mm, the 17-70mm ƒ/4 becomes a worthy upgrade.

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