[Redundant Banker]

I have ordered a Sigma 18-250mm f3.5-6.3 DC OS HSM for use as a travel lens on my K-r. I know that I cannot use both the OS on the lens and the IS on the camera at the same time; it has to be one or the other. The question is, which is better?

[Adam]

I would stick to the in-camera solution. There are a few OS vs. SR threads on the forum:
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/159828-os-shake-reduction.html
https://www.pentaxforums.com/forums/pentax-beginners-corner-q/115170-body-sha...pros-cons.html

[JinDesu]

My understanding is that in that focal range, OS isn't that much better than IS. However, OS does take up more energy than IS, and if you go use timer mode on a tripod or remote mode on a tripod, the camerea automatically turns off IS. So if you have OS on and you don't pay attention, your tripod shots may be blurry.

[panoguy]

I have ordered a Sigma 18-250mm f3.5-6.3 DC OS HSM for use as a travel lens on my K-r.

My understanding is that in that focal range, OS isn't that much better than IS.

Maybe not from 18-100mm, but from 100-250mm the in-lens OS will be more effective. I've seen this in practical use with Sigma's OS system, which, to be fair, is much louder and slower to react than Pentax in-body SR... so for the OP, it actually won't add too much, or detract too much as long as you remember to turn it on and off.

[Redundant Banker]

Thanks everyone!