HD Pentax-D FA 70-210mm F4 ED SDM WR

Construction and Handling

The HD D FA 70-210mm F4 is a tele zoom lens of relatively large size. It is significantly larger than many consumer zooms, while remaining much smaller than the higher-end 70-200mm F2.8. The one-stop smaller aperture makes a visible difference; while still larger than the average lens, the 70-210mm F4 remains compact enough to be easily carried around, even when travelling.

This section will give you a complete tour of the lens, from every angle. You will also see the lens alongside other comparable lenses and mounted on various camera bodies.

Front Element

The front of the lens is dominated by the large front element. There are no marks or indications at the front.

The front element is covered by the Super Protect (SP) coating, which allows easier cleaning and helps to repel dirt and oil. This is no mere gimmick; the SP coating really is an improvement over regular coatings and practically guarantees the removal of any lingering dirt or dust.

The lens uses a 67mm filter thread. This diameter is found on several comparable Pentax lenses, such as the DA* 60-250mm.

The lens cap is the standard Pentax plastic pinch design.

Lens Body

The body of the lens is made of plastic. This does not mean that it is cheap. It feels tightly assembled and robust. Still, at this price point Pentax usually uses metal for the lens barrel.

Starting from the base (at the lens mount) and going up, the lens tapers outwards from the mount, to reach a cylindrical shape. The first section bears the minimalist printed lettering indicating the focal range and aperture. To the left (as seen from the top) is the silver D FA logo.

Right above is a slightly narrower section, looking conspicuously well suited to accept a tripod collar (more on this below). Higher up is a third segment, this one showing the Pentax name, again printed. On the left side are two switches. The first is the AF-MF switch, and the second is the focus limiter. In its full mode, it allows the lens to focus from 95cm to infinity. Using the limiter allows the user to constrain the AF range from 0.95m to 2m or from 2m to infinity. This can speed up AF in many situations.

Next is the focus ring. With a throw of 180⁰, it offers plenty of control for fine-tuning the focus point. The ring comes to soft stops at both ends (it continues to turn, but with a higher friction and without impacting the focal distance). Close to the focus ring is a window showing the focus distance in meters and feet.

Near the front of the lens is the zoom ring. With a throw just shy of 90⁰, it allows quick adjustments of the focal length. About three quarters of the throw covers the range from 70 to 135mm, and a quarter covers from 135mm to 210mm. The zoom ring is wide, at 3.9 cm, with the center 2.8 cm textured. The zoom ring also includes the ubiquitous green ring, and the lens name.

The last section holds the lens hood and is slightly narrower than the rest of the lens.

The back of the lens shows the serial number, the “Made in Vietnam” label and the CE identification.

The lens does not extend when zooming.

Aperture

The Pentax D FA 70-210mm uses 9 curved aperture blades. Since it uses the KAF4 mount, it is not possible to see the aperture blades with the lens unmounted.

Lens Mount

The lens mount is metal. Anything else (namely, plastic) would be surprising at this price point. The lens is protected against water ingress.

The lens uses the most recent iteration of the K-mount, called KAF4. This means that the lens will not be compatible with cameras older than the K-50, as it lacks a mechanical link to control the aperture.

Instead of being round, the back of the lens shows a flange in the shape of a truncated oval.

Lens Hood

The lens ships with a plastic, petal-shaped lens hood. Surprisingly, the hood lacks the removable window allowing filter access which is normally found on almost every Pentax hood.

The hood reverses for storage. When reversed, it hinders access to the zoom ring. This is one reason to prefer zoom rings near the base of the lens. The trend of having the zoom ring near the top is more and more common, however.

Tripod collar

As mentioned above, the 70-210mm F4 does not ship with a tripod collar or foot. Given its relatively low weight, at least compared to other fast zooms like the D FA* 70-200m F2.8 and DA* 60-250mm F4, this is not particularly worrisome. Carrying the lens and camera combo presents no problem.

However, for users who desire the option of using a tripod collar and foot, the presence of a wide, narrower section near the base hints at the option of installing a third-party tripod collar.

Indeed, the Tamron Tripod Mount M for 70-210mm tripod collar (model A034TM), available separately for around $120, is a perfect fit for the Pentax 70-210mm. This collar is entirely made of metal, and very well made, if a bit minimalist.

The foot even includes bevels compatible with Arca-Swiss tripod heads on the four sides. The long axis will be too long for most Arca-Swiss clamps.

The collar perfectly slides into the groove on the lens body.

The tripod collar fits like a glove on the D FA 70-210mm.

There are only two downsides to using the collar. The first is that, in order to remove the foot or collar, the screw must be completely removed. This is a departure from the usual Pentax way, which is to only remove the foot (making the process simpler and faster).

The second downside is that the collar lacks any kind of click or feedback to position it horizontally or vertically. It only features a small white dot, but the lens body is devoid of any alignment markings.

It must also be noted that this tripod collar brings a weight penalty to the assembly.

Similarities with the Tamron 70-210mm F4

The Pentax 70-210mm clearly shares many characteristics with the similar lens from Tamron. The external body is extremely similar: the general shape is the same, the same tripod collar fits both lenses, the switches are identical to the Tamron lens while being different from the typical Pentax controls. The hood lacks the common Pentax window. All of this hints at a shared background, and probably shared production tools.

On the other hand, many elements are genuinely Pentax. The presence of the red seal at the base, the color of the lettering, the texture and finish of the rings are similar to other Pentax lenses. The coatings are also resolutely Pentax.

It must be remembered that, even though it is obvious that the Pentax design has some roots coming from Tamron, one should not conclude that this is purely a Tamron lens. Tamron’s exact involvement  is unknown and could range from licensing the design and manufacturing tools, to completely producing the lens under contract from Pentax. In any case, having Tamron involved in the lens’ design is not a bad thing; the company’s 70-210mm is well-regarded, and Pentax’s version of Tamron’s 24-70mm and 15-30mm are excellent lenses in their own right.

Compared to Other Lenses

Here is the D FA 70-210mm next to the Pentax D FA 28-105mm, a likely companion, and the DA* 60-250mm, an obvious comparison point.

Since the D FA 70-210mm zooms internally, the above size comparison doesn't tell the whole story. The following animation illustrates the size relation with the DA* 60-250mm with the latter zoomed in and out.

Mounted on Camera

Below are images of the 70-210mm mounted on a Pentax K-3 (APS-C; left) and a Pentax K-1 (full frame; right).

Verdict

The Pentax D FA 70-210mm checks all the boxes of what a moderately fast zoom should offer: a well-controlled body weight, comparatively compact size, high-quality assembly, weather resistance and a few external controls. The presence of a focus limiter is particularly welcome.

Despite all of this, the lens lacks the wow factor that some users will expect at this price point. The plastic shell, lack of a tripod foot and hood filter window, as well as the printed lettering suggests a consumer-grade product. This does not mean that the lens is any worse, or that its optical qualities will be any lesser, but the choice of materials and small design details are not on par with our expectations given the price point.