Pentax SMCP-DA 17-70mm f/4 AL (IF) SDM Autofocus Lens for Digital SLR

Model #21740

Pentax Warranty - USA Version
Pentax 21740 1
Pentax 21740 1
Pentax 21740 8
Pentax 21740 5
Pentax 21740 3
Pentax 21740 6
Pentax 21740 9
Pentax 21740 2
Pentax 21740 4
Pentax 21740 7
How it works
  • You name the price you want to pay for a product.
  • We send your offer to a network of Certified Retailers.
  • If the retailer likes your offer, you get that price for the product.
Greentoe Guarantee
  • All Products are New and from Manufacturer Authorized Retailers
  • 30 day return policy
  • Free Shipping
    No Additional Fees

Product Back-Ordered

We are sorry. At this time, we are not accepting offers on this product. Please click the button below to be notified when our retailers get it back in stock.

Thank you! We will be in touch. Something went wrong. Please try again later.


Dimensions (dxl) Approx. 3.0 x 3.7" (7.62 x 9.40 cm)
Filter thread 67 mm
Weight 1.07 lb (485 g)


Focal length 17 - 70 mm
Comparable APS-C Focal Length: 25.5 - 105 mm
Magnification 0.31x
Aperture Maximum: f/4
Minimum: f/22
Minimum focus distance 11.04" (28.04 cm)
Format compatibility Pentax Digital (APS-C)
Camera mount type Pentax K
Angle of view 79° - 23°
Maximum reproduction ratio 1:3.22
Groups/elements 12/17
Diaphragm blades 7


Image stabilization No
Tripod collar No
Autofocus Yes
Expert Reviews
Pop photo.32824722
10 February 2010

Pentax describes the 17-70mm f/4 lens as a “standard lens with extra zoom,” a cute catch phrase. But “standard zooms,” as they’re called, are one of the most popular lens groups.

5 January 2016

The lens is a very good performer in many ways, with just a couple of weak areas as mentioned, designed with the central performance given priority. The questions to ask revolve around whether or not lenses from the same range that have wider ranges, sometimes better sharpness, faster focusing and...

  • +

    Very good central sharpness, Excellent central CA control, Focuses very close, QuickShift focusing available, Silent AF, Constant aperture design

  • -

    Lower edge sharpness, CA at edges at 17mm, AF not the fastest, No weather resistance

User Reviews
B h photo.32817553
16 February 2017

I bought my DA 17-70 used about 4 years ago. I have used it often during that time on a K20 and K30 body without any SDM issues. Maybe I have been lucky or maybe the failures are actually the exception, who knows?

27 July 2016
10/10 complaints

B h photo.32817553
2 June 2015

I did purchase this lens in 2010. This image quality is very nice but I did replace the SDM 2 times since. I probably should have purchase the sigma but... I must agree with the fact that pentax should recall all those SDM lens and find a real fix because this is not good for a reputation.Pentax K5...

14 July 2014

Fantastic lense well made good in all light levels with F4 and water resistant too :-)

B h photo.32817553
28 November 2013

This Focal length is ideal for the kind of photos that I take which is why I purchased it. Now I may have gotten a bad one but it's auto focusing has never been satisfactory and then the motor died. I have used the lens on K20 and K5II bodies with the same results. ......

B h photo.32817553
9 November 2013

Let me start by saying I'm a big Pentax fan. I've owned 3 camera bodies and own 7 different Pentax lenses. Great equipment but the SDM motors on these lenses have been an utter failure. The fanboys and Pentax PR people will tell you the issue has been fixed but don't believe it.

17 March 2013

It has a constant large aperture/4 which is quite nice and the focal length can meet my daily need . I've heard that the focusing function is not so good, but as I tried, focusing is not bad.

15 March 2013

I found I used it a lot in the studio and miss it now I've dropped it :( It's a little soft, but still very usable even for commercial work. I dropped mine from about 6 inches onto a laminate floor, which is fairly forgiving normally, but despite landing on the hood, something broke inside and that...

13 February 2013

Bought as am "everyday" lens for a K30. The range is perfect ( approx.26 -105mm in old money) for the great majority of the shots I take and I therefore chose this lens over the 18-135 feeling that the loss of far end telephoto was a worthwhile trade off against the mixed reviews that that lens has...

17 December 2012

This lens has a very versatile range, from 17-70. You may be put off by the f4 aperture, but it is pin sharp wide open, unlike the sigma 17-70 at f2.8 which is sloppy and soft. It has some weather sealing, not for storms but for light rain it will be sealed.

Product Highlights
  • Zoom Super Wide-Telephoto
Average Expert Score
Average User Score
In The Box
  • Pentax SMCP-DA 17-70mm f/4 AL (IF) SDM Autofocus Lens for Digital SLR
  • 67mm Lens Cap
  • Rear Lens Cap
  • PH-RBM67 Lens Hood for the SMCP-DA 17-70mm f/4 AL (IF) Lens
  • 1-Year Warranty
Still Have Questions?
We can help via Live Chat, Email or you can call us 1-888-840-0464


Please log in or sign up to continue


Validating Credit Card...

It will not be processed until the offer is accepted by a merchant.

Notifying Retailers...

Notifying our merchants and checking to see if they accept this offer.

Offer Submitted!

3-digit code in the back of your credit card