Pentax DA 16-45 f4

The first of the DA series of lenses designed for APS-C digital cameras, the Pentax DA 16-45 f4 could be regarded as a mid-range offering to fill the popular focal ranges between wide angle and short telephoto. The lens is generally well regarded. Some have even gone so far as to compare it with professional standard lenses such as the Pentax DA 16-50 and the Canon 17-40 f4 L. While the 16-45 is clearly not a professional grade lens, it is still very good lens that can produce very fine images. It’s main weakness is mediocre build quality. The lens extends at the wide end of the zoom and extending barrel is made of plastic and has a bit of a wobble. Unlike most of Pentax’s better zoom lenses, the 16-45 is not an internally focusing lens. This means the focusing is slightly (very slightly) dampened; or, rather, there is some friction of plastic parts rubbing against each other. But despite lack of internal focusing, the filter ring does not move when focusing.

I’ll admit that I did not have particularly high hopes for the lens in terms of resolution. I had done an immense amount of research on the lens before purchasing it and expected the lens to be inferior, in respect to resolving power, to the DA 12-24 at 16mm. I particularly expected there to be softer corners. This, however, proved not to be the case. Consider the following image, taken at 16mm with the Pentax K-5 at f8:

Now take a look at a 100% crop of the corner:

Now really this is really very good, nearly as good (if not just as good) as you might find with a lens such as the DA 12-24, which is known for its outstanding corner to corner resolution. And this corner sharpness is maintained pretty much throughout its range (providing one stops down to f8 or so).

According to various resolution tests published on the web, the 16-45 performs at its best around 24mm, before losing a bit of resolution at the long end. While I haven’t done any specific tests on the lens, in just ordinary everyday use, I can’t say I’ve noticed much difference between the wide, middle, and long ends of the lens. At f8 it performs pretty much the same throughout its range. Perhaps there’s a slight loss of resolution between 35 and 45mm. But it’s very slight and hardly noticeable in “real world” use. Below are some random samples, all shot at around f8:

@ 20mm—


@ 24mm—

100% crop—


100% crop—


100% crop—


100% crop—

Color rendition on the DA 16-45 is very good, but to my eyes not quite at the level of Pentax’s top glass. Nonetheless, the differences are not easy to illustrate; and attempts to compare similar images from each lens lead to ambivalent results. Compare the following two crops of stained glass window, the first (on the left) taken by the DA 12-24, the second by the DA 16-45.:

It’s very difficult to make any definite conclusions from these two crops. I’ve tried to make the 16-45 crop look as close to the 12-24 crop as possible, but even here I wasn’t entirely successful. In any case, out of the camera, the DA 12-24 was significantly better, but a bit of PP TLC and the differences aren’t all that significant. I still tend to prefer the color rendition of the DA 12-24. There are subtlety to tones and hues I could get out of that lens that I can’t quite match with the 16-45 (although the results of the 16-45 are always very good).

Since I use the DA 16-45 almost exclusively for landscape (with an occasional incursion into architecture), I almost never use the lens wide open; so I can’t really comment on how well it performs at f4. I would suggest that if low light or narrow DOF are an objective, one may be better off with the Tamron 17-50 f2.8, which sells for not much more than the DA 16-45. The Pentax lens really is at its best as a landscape/architecture lens, where it can be used at f8 in conjunction with a tripod. There it performs quite well, just a notch or two below what a decent prime lens might achieve. It may not be a great or superlative lens, but it’s very good nonetheless. I prefer using prime lenses where possible. But when, as sometimes happens, I absolutely need focal range versatility for landscape photography, the DA 16-45 is the first lens I reach for.

More images from the 16-45:

@ 16mm—