Reviews and Problems with Pentax SMC DA 17-70 mm f/4 AL (IF) SDM
Showing 1-10 of 55
17 November 2014
Excerpt: The smc Pentax-DA 17-70mm F/4 AL IF SDM is a compromise model which does not make much of an impression. Certainly the manufacturer tried to develop a convenient lens with a fairly wide range of focal lengths and a constant maximum relative aperture F/4 and substantially very good sharpness. But in reality the lens is not sharp enough near the 70mm, has SDM motor problem which affects the accuracy of autofocus and the bokeh is neutral and leaves something more to desire.
Pros: very good sharpness, constant maximum aperture F/4, wide focal lengths range
Excerpt: Optically, this is a very good standard zoom lens. For mid-aperture shooting, perhaps only the DA* 16-50 can beat it. The lens is fairly sharp and impressively contrasty. Color rendition is good, but not quite at the level of limited or star glass, or of the DA 12-24 and DA 10-17. It's color rendering is a tad on the warm side, closer to Pentax telephoto glass (like the DFA 100 macro and DA* 300) than Pentax wide angle glass.
Pros: Loads of microcontrast, fairly sharp, decent color rendition
Excerpt: If this lens were 17 to 50, I would probably give it a 9. The issue I have with this lens is autofocus of distant images from 50 to 70 mm. I don't know why this is but on both my K10D and K5 I have the same issue with this lens. Zoom wider than 50mm and the autofocus is perfect, quick and accurate but above 50 mm on a distant subject, it sometimes just cannot get a fix on a subject near infinity and just does not autofocus reliably.
Pros: Versatility, sharp for a zoom, build quality
Excerpt: I bought the lens used from another forum member here and used it on a K100d Super until very recently when I bought a K-5. The lens SDM worked well on the camera, as advertised. Before this lens, I used the 18-55 II, which is quite good, but this one is well worth the extra cost. The sharpness is better across a broader range, but the most noticeable change is the rich, vibrant colors. The colors are richer with this lens than they were with a circ polarizer on the II.
Pros: Colors!, Sharp, Great range, Constant aperture
Cons: Harder to focus manually, Fails to lock focus infrequently
Excerpt: Three months have been using this lens. First to K-7, now with the K-5. Somewhat surprising is the amount of criticism about the autofocus. My copy everything works fine. Focuses very quickly and accurately. Bought a used lens, which has already been 4 years. And not at all disappointed with the quality of the picture ...
Pros: sharp, picture quality, constant aperture
Cons: loose front lens. I sometimes get worried about it. low luminosity
Excerpt: I got this lens to replace my 18-55 WR. The autofocus tended to hunt and so I sent it in for repair. That cost me ~100$. Next the SDM motor failed twice within the hour I got it back from service. The lens has been repaired under warranty both times. However i could not trust this lens anymore and therefore sold it.
Pros: sharpness, contrast, zoom range, constant aperture, very good image quality at f/4 already
Cons: SDM failed multiple times on my copy, autofocus tends to hunt at 35-70mm range, CA's could be a little better but can be easily corrected in pp
Excerpt: This is my workhorse lens, its quite versatile, constant aperture is very convenient and is reasonably sharp, although not up to standards set by limiteds. But nobody expects this lens should compete with limited primes for IQ.