Evaluating what my favourite lenses are early in 2025 made me realise just how my tastes have changed in the last twelve months. A little over a year ago I had no idea that I was to move from an admirer of the Pentax DSLR system to a user. Writing this article in April 2024 was the defining moment and catalyst for stepping into the world of Pentax. At the time of writing about the 31mm Limited, my interest in small, precision made lenses was rekindled, influenced by my appreciation of the Olympus Zuiko lens system used when I shot film.

I enjoy my Pentax DA 20-40mm F2.8-4 Limited zoom and it has gradually sneaked up my list of most used (and appreciated) lenses, pushing out some of my Leica lenses that were important to me not too long ago.

From what I can glean, the Pentax Limited series has a tendency to do this and, as is often the case, one is not enough. Many Pentaxians collect the whole series (1 x DFA, 3 x FA and 6 DA models are in production). As I write this it is not my intention to collect them, but simply a matter of picking out those that will be of most use. And as a lover of short telephotos, I was immediately attracted to the DA 70mm F2.4 Limited.

Design and Handling

Until I received this 70mm, I was convinced that the smallest lens in this class of telephotos was the Olympus OM Zuiko 100mm f2.8. That 100mm was one I dearly loved and even though it was a compromise between optical perfection and size, found that it was often used as a sole ‘walk around’ lens. Minus it’s lens hood, this 70mm is even tinier than the venerable Zuiko, at just 63mm long. The screw-in hood adds a nominal amount to the length and is a telescopic construction that provides additional shading from harsh light sources. A beautifully machined aluminium push-on cap fits over the lens when not in use. The cap is felt lined and has the Pentax name embossed stylishly across the front, exhibiting nice attention to detail that in turn gives it a premium feel. Stood next to my HD Pentax-DFA* 85mm F1.4 SDM AW, it is hard to believe that both lenses fulfil the same basic criteria.

Unlike the DFA* 85mm, the optical design is pretty simple, consisting of just six elements in five groups, none of which are manufactured from exotic glass. But it is treated with Pentax’s latest HD coating that repels moisture and oils from the glass surface. The coating is also very tough so can be cleaned with confidence. At 130 grams, It is a featherweight, perfectly aligning itself with the design philosophy of the DA Limited lens line-up. Such a diminutive size and the aluminium construction make it feel like a jewel, balancing beautifully on a K3 mkiii body.

A nice touch on all of the DA Limited lenses is it’s ‘Quick Shift’ ability, allowing focus to be adjusted manually after autofocus acquisition. It is not something I use often as I find autofocus to be accurate enough. However there are scenarios, particularly when working at open aperture with telephoto lenses at close distances, where I find myself refocussing slightly to include a detail that I may have missed during autofocus. Also apparent on all later generation DA Limited lenses are rounded aperture blades. This contributes towards a ‘smooth’ bokeh rendering at wider apertures, but may be considered detrimental as far as stopped-down starburst effects are concerned, as straight aperture blades are deemed to give better results.

DA Limited lenses also rely on a screw drive motor housed in the camera body to drive autofocus. Compared to the latest generation of lenses which use near silent ultrasonic motors, they feel a little archaic. That being said, autofocus is reasonably accurate once the lens has been calibrated with the camera body. 

The HD PENTAX-DA 70mm F2.4 Limited ships with a small leatherette storage pouch that takes up little space in a bag or pocket. Unlike some of my other lenses (I’m thinking of my Pentax DFA* 85 or Leica SL Summilux 50) there is no excuse for leaving it at home.

In Use

The HD PENTAX-DA 70mm F2.4 Limited, like all DA badged lenses, is designed for use with APSC size sensors (although some can be used successfully on 36 x 24mm sensor cameras), so the field of view equates to approximately 107mm - very close to my beloved Zuiko.

Attached to my K1 mkii some vignetting wide open is present, which is hardly surprising given its smaller image circle. I purchased this lens for use with my K3 mkiii and tried it on the K1 simply our of curiosity. For the purpose of this review I will share only my experiences with it attached to my K3 mkiii, unless stated otherwise.

At 0.7metres, the minimum focus ability of the lens is nothing outstanding. Due to the telephoto ratio it is possible to for a larger subject to fill the frame, but falls well short of having any true close focus or macro capability. Images shot at minimum focus are very good regardless of aperture, with the exception of a little softness  at the edges at f2.4. Depending on how you roll with this effect is a personal matter, but I see this as a creative opportunity. If I need close up, wide open edge to edge sharpness, there are other tools I can use.

Something I have noticed is a little softness across the entire frame at infinity and wide open. It seems to be consistent regardless of subject matter, lighting or contrast. I am not sure if it is just my example of the lens that exhibits this but I always close it down to f2.8 to alleviate the problem. 

Aside from the above caveats the HD PENTAX-DA 70mm F2.4 Limited is an excellent performer with sharpness reaching its peak at around f4.5 to f6.3. It is excellent at other apertures but if I am looking to get optimal sharpness from it, I use a setting between these two values.

Being a short telephoto with 9 rounded aperture blades, the bokeh is very much to my liking. There is a softness to it that is difficult to describe, other than to say it is very much like other Pentax Limited lenses and maybe contributes to the much mentioned ‘pixie dust’. One thing to look out for though is Longitudinal chromatic aberrations which can be very visible in out of focus areas. I have found green LoCa to be the most problematic and while I can remove some in post, I resort to reducing the background texture to help hide it. Purple LoCa is also visible but I have not been troubled by this as much as green.

Lateral chromatic aberrations in the green and purple parts of the colour spectrum are also apparent and, typically, present themselves more when the lens is used wide open in situations of harsh contrast. For the most part they are easily removed during post processing.

As bokeh is very much a personal thing, it is difficult to quantify its appeal. But for my own personal taste I have found it to be pleasing enough and not become too much of a distraction from subject matter. It is best described as gentle, with a smooth fall off from what is in focus. At no aperture have I found it unacceptable.

As mentioned earlier, and typical of all DA Limited prime lenses, the 70mm uses a screw drive mechanism to achieve focus. Compared with most modern lenses there is no denying it is a tad noisy. This could be perceived to be problematic if used in a quiet environment, so I switch it to manual focus when needed. This reduces the motor noise to a minimum and negates the possibility of the lens hunting if focus is missed. Quite why Pentax never updated the autofocus technology of the DA Limited primes to use the quieter motor found in the DA Limited 20-40 is a mystery as this would really bring the lens up to date.

In Conclusion

Having used the lens for almost a year, I have to admit it to being a little ambivalent about it. I love the beautiful build quality and its tiny size. I have no excuse for not taking it along when I am shooting with my 20-40mm zoom as it makes the perfect short telephoto companion. Results from it are good enough with the exception of wide open at infinity. Don’t get me wrong, I have made some beautiful images with it. But it simply does not ‘grab’ me like other short telephotos I have owned. Maybe this is due to using the DFA* 85mm f1.4 which is particularly good. However, apart from this and the 70mm operating at similar focal lengths and using the same mount, they have nothing in common and are built to address two very different market segments.

Would I purchase the lens again? That is a difficult question to answer. It fulfils a niche in my lens arsenal and will inevitably lead to its continued use. But I cannot help thinking that it would be interesting too use the legendary FA 77 Limited lens for a similar period of time and see if it really is more than a sum of its parts and deliver the esoteric experience that personally eludes me with this diminutive 70mm.

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