Pentax DA 35mm F2.4 vs 40mm XS vs 40mm Limited

Design and Handling

DA 35mm f/2.4

The DA 35mm f/2.4 is a very inexpensive lens by Pentax standards (retailing at $179.95 in the USA), and its look and feel ultimately reflect this discount. In your hand, the lens is light and toy-like—an impression that’s reinforced by the plastic mount. The all-plastic body is mostly a smooth matte black, with ridged plastic in some places to provide grip as you mount and unmount it from the camera. As with the other lenses coming out of Pentax recently, the company name and focal length are printed in large, somewhat garish (in our opinion) letters near the mount, and more detailed lens specs are also (in smaller letters) emblazoned just below the focusing ring.

Despite the cheap look, feel, and materials, the lens appears to be built to high standards. There is no observable play in the construction at any point, and the plastic appears to be of a very durable variety. As for plastic mounts, we have never been of the opinion that they are inferior to metal mounts in everyday use—it's simply that the presence of a plastic mount is typically taken as evidence of corner-cutting. The focusing ring moves smoothly and is actually quite well damped for a consumer autofocus lens. Unfortunately, its short throw (though it enhances the AF speed) makes manual focusing more difficult. It also lacks a focusing scale, which will be a disappointment to street shooters, among others.

DA 40mm f/2.8 Limited

The DA 40mm f/2.8 Limited is a lot smaller, a little slower (in terms of max aperture), and a lot better built than the 35/2.4. Made entirely of precisely machined metal, it’s a far superior bit of engineering. It's also a lot more expensive, going for $369.95 as of this writing. The members of the Limited line have often been called "jewel-like," and the DA 40 is perhaps the most beautiful and impressively designed of all. The construction is impeccable, with no play whatsoever. It's also quite the looker on-camera (a K-5, in our case) with its engraved name, focal length, and aperture info. This information appears on both the bezel around the front glass and on the screw-on hood.

Like other DA Limited lenses, the 40mm f/2.8 Limited includes quick-shift focusing, allowing you to override the autofocus mechanism at any time, and it also has a proper distance scale. Manual focus is very smooth, though once again the focus throw is very short, making precise focusing more difficult than it otherwise would be. Ergonomically, the lens is so compact as to be a bit difficult to grasp. Getting it mounted and unmounted can be a small challenge, and you’ll be using your very fingertips to focus. Really, it works best as an AF lens.

DA 40mm f/2.8 XS

Though extremely similar (perhaps even identical) to the DA 40/2.8 Limited in terms of specs and optical construction, the DA 40mm f/2.8 XS is even more compact (9.2mm vs 15mm thick) and more lightweight (1.8 oz. vs 3.2 oz.). At a price of $246.95, it also shaves more than $100 off the cost of its fancier brother. Its body is entirely plastic, aside from the somewhat surprising inclusion of a metal mount, but it feels very well built all the same.

The lens is so small that there’s not really much to comment on. The body is comprised solely of the focusing ring and a narrow fixed band that gives you something to grasp as you screw it onto the body. The nine aperture blades on this model are curved to produce a more circular opening as the lens is stopped down. This is one of the few significant differences between it and the earlier DA 40/2.8 Limited, and one whose effects we’ll examine during our bokeh test.

According to Pentax literature, the lens’s external appearance was designed by Marc Newson, and it’s true that it mates quite well with the Newson-designed K-01. On the K-5 it produces a slight aesthetic clash, but being matte black and so incredibly thin, you’re more likely to forget it’s even mounted than to spend much time worrying about its looks.