Originally posted by panonski correct - I was shooting with 14Mpix size M*** .
Why I'm counting pixels .. Because I often shoot people, and sometimes I count on SR to get lower Iso...
I can easily go with 1/30 to shot the people, but I was wondering how low i really can go.
Firstly, 1/30s is too low in my experience when shooting people. Even when they're standing still or seated, there is simply too much possibility for very slight movement in the subject. You might get some sharp shots at 1/30s, but you'd be better off at 1/60s, and much better off at 1/100 - 1/125s. This has nothing to do with SR, but with the ability to freeze motion - a very different issue, as I'm sure you know.
Originally posted by panonski It seems for me, the blur becomes visible at speed twices low then recomended speed without SR on.
to be said - that means for 70 mm end - 1/100 shuter speed - am I right here ? From film era - it was valid rule how long is your lens lengt - that' how your lowest shutter speed can be.
It's true .
so, Im closeto 2 stop down from that when I get acceptable result with SR turned on - with 1/30 - 70 mm
Using the rule
1 / (focal length x crop factor), on APS-C, hand-holding
without SR you should be able to get sharp shots of static objects at 1 / (70 x 1.5) = 1/105s... so, yes, 1/100s should be fine. Of course, some people will need a faster shutter speed than this if they're not steady enough, while some will be able to go considerably slower if they are steady and have good technique in their hold of the camera and breathing.
Three stops of SR advantage should, in theory, allow you to shoot at 1/13s instead (the K-3 is good for 3.5 stops, the K-3II - allegedly - for 4.5 stops). But this assumes you're getting blur-free shots at 1/100s without SR, and is for
absolutely static subjects. In reality, 1/13s is simply way too slow for capturing people.