Sigma 17-70 "Contemporary": compatibility problems with Shake Reduction

<p>There appears to be a problem with the Pentax version of this lens. Under 31mm it is communicating the wrong SR Focal Length by a very large margin. This introduces blurring when SR is on. Please check the following thread about it on PentaxForums.com. It has been verified by a number of users with the lens on different Pentax models.<br>

<a href="http://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/285104-sigma-17-70-contemporary-compatibility-problems-shake-reduction.html" target="_blank">http://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/285104-sigma-17-70-contemporary-compatibility-problems-shake-reduction.html</a><br>

If you own the lens, please check it out. Also, I would suggest that you contact Sigma to inform them of this problem so that that can issue a firmware fix to send the right SR Focal Length.</p>

<p>Downloaded the latest version of the PhotoMe...... This software hadn't this particular info at all to give from pictures taken at 17mm with either of my cameras....K-5 and K-3 PE...<br>

So as for now I just did a <strong>very very simple</strong> test.... using my K-3 and the lens at 17mm with shutter at 1/15...<br>

With simple I mean that I only used the third step with the on/off lever on the camera.<br>

Closing in and comparing pictures gave actually this result...<strong>SR on</strong> gave <strong>less "blurry"</strong> picture....<br>

But as I wrote this was a very very simple test... I do understand that I have to take real pictues for comparing....<br>

I do wonder though if the firmware in camera has to do anything with this problem...<br>

My K-3 PE have firmware 1,11........... </p>

<p>That's interesting.<br>

Other users found that in PhotoMe they were able to see SRFocalLength in the Manufacturer Notes field for the K-5, K5-ii and, I think, some other models, but it was not visible for the K-3. And, the values passed were wildly off under 31mm.<br>

Everyone on PentaxForums.com who did the 1/15 sec test found that sharp results were possible at 17mm without SR, but much more unlikely with SR. It's interesting that you got a different result.</p>

<p>Today (saturday) I got some confirmation to my previous text.... Took some pictures to be able to compare <strong>SR on</strong> or <strong>SR off.</strong>... The camera was set to 1/50 (f8) and the lens in this case to 28mm... Viewing those two pictures at the same time on my monitor <strong>clearly</strong> showed that with the <strong>SR off</strong> the picture was blurrier.....<br>

So, once again.....This particular Sigma lens might actually work correctly when your K-3 has firmware 1,11........well, <strong>mine</strong> actually seems to do that. </p>