View Full Version : Sigma HSM and Pentax AF Compatibility

11-05-2010, 11:09pm

This is probably a question for Kym? Does the k7 support HSM focusing on Sigma lenses or do all Pentax mount Sigma lenses come without HSM so that AF works. The local camera shops on the Gold Coast don't stock much in the way of Pentax hence they haven't been able to answer this question for me.



JM Tran
12-05-2010, 1:07am
the K7 will support HSM for all newer Sigma lenses with HSM for Pentax K mount

early generation Sigma 70-200 f2.8 for example, came with HSM for Canon/Nikon etc but in Pentax mount the HSM was removed for the normal screw driven AF

12-05-2010, 8:47am
Jackie is 100% correct.

The K10 and the K100D Super have SDM and therefore HSM support.
Everything since then as well.


In January 2008 Sigma announced the availability of lenses for Pentax which feature HSM (HyperSonic Motor) focusing, similar to Pentax's SDM technology. There is a significant difference: The Sigma Pentax HSM lenses won't autofocus with any Pentax cameras that aren't SDM compatible. This includes the ist-D, ist-DS/DS2, ist-DL/DL2, K100D, K110D and all film cameras. If you use one of these older Pentax cameras with a Sigma HSM lens you'll only have manual focus.

12-05-2010, 11:39pm
Thanks Kym and Jackie,

much appreciated



Ozzi Paul
21-05-2010, 10:35pm
I have the Sigma 70-200 f2.8 HSM II on my K20D, it works great and really helps the speed of focus. Not sure how fast the AF is on the K-7 but its not great on the K20D so the HSM makes a big difference.