Shake Reduction and 'action' photography

I have always had SR activated on my K-5 (apart from tripod use), but I'm now wondering whether there are times when it's better not to use it.
In particular, I'm thinking about motor sport photography, where I'm tending to use higher shutter speeds with a longer lens (300mm).
I have to admit to (so far) not really looking for the green 'hand' icon, as I'm concentrating more on panning and framing of the shot, and tend to make the assumption (perhaps incorrectly) that the SR will normally be fast enough to keep up with me.
Am I better off de-activating the SR, so that it does not blur the shot if it's not ready, provided that I am using high enough shutter speeds?
I'd be grateful for your opinions.

Off is best if shutter speeds allow. Mentioned it a couple of weeks back https://www.pentaxuser.com/forum/topic/a-few-with-the-da-300---f4-40397

Thanks Alan, I missed that post.

Have done speed boats, various air shows and a couple of rallies ... SR has always been left on with to effect on the final pictures (as far as I can see anyway)

Sigma's optically stabilized (OS) lenses have a 3 position OS switch.

Off, 1 - both vertical and horizontal planes are stabilised, 2 - only the vertical plane is stabilized, used when panning.

It would be nice if Pentax would add this functionality too. It does make a difference.

So it sounds as though the implication of your comment about the Sigma lenses OS is that it might be better to turn off SR on the Pentax when panning?

SR has to take a moment to lock, so wouldn't switching it off be better for fast focusing for sport and wildlife?

Yes it might be worth turning SR off in a sports scenario.

All I can suggest is that you try both.

I do a lot of stock car racing photography, track side as the club 'tog, so I'm quite close to the action. This means that I'm usually panning quite fast to keep up with the cars and the SR/OS horizontal stabilization keeps trying to compensate.

My personal experience with my Sigma 70-200 lens is that I get sharper results using mode 2 on the lens than I do when using mode 1, and in-body SR turned off. Mode 1 OS on the lens being equal to in-body SR turned on, albeit implemented differently.

I'm sure Pentax could easily add this feature and even have it change according to the cameras orientation, something that in-lens stabilization can't do.

Thank you all for your comments. I'll be trying it out on Sunday at Mallory

Yes it would.

I do a lot of impulse snaps of people and I've had sevral shots which have SR Blur due to this.

You can see the lag on SR by switching to live view and quickly panning the camera and then stopping.


Note: switching SR OFF doesn't solidly clamp the sensor rigid though ( LV can show this too ). I wish it did

I wondered about this and out of curiosity I checked the exif data and frame numbers of a shoot of motor bikes I done in March. I took just over 500 shots in 20 minutes, that is less than 3 secs per shot and they were all framed and shot singly.
I think I deleted about 24 because of focus problems,I would be happy to leave the SR on.

John

I've never noticed any real difference either. I try to follow conventional wisdom and turn SR off or select the correct mode on the 150-500, but on the occasions I forgot to do this it didn't seem to make a difference. I think there are many more significant factors to worry about, but it will depend on the subject matter.

As a few of you know I photograph BriSCA F1 and F2 Stock Cars, plus a few other forms of short oval racing.

I think I bought up the subject of SR on or off a while ago, I have now done quite a few tests and my personal conclusion is this.

The results differ between my K5 and my K5II.

K5 + 300mm DA* ~ I have the SR on ( SR on, pin sharp / SR off blurred )

K5II + 300mm DA* ~ I have the SR off ( SR on, blurred / SR off pin sharp )

But...when using my 60-250 DA* I have to have the SR off on both cameras.

Why they should differ I just don't know.

Regards,

Chris.

Quite a few differing opinions.

It's very curious how inconsistent everyone's experience with this is, and especially your experience, Chris, with different body/lens combinations.

Does anybody know - is the SR linked to the AF at all, or is it a completely independent system? I'm wondering whether that might be a contributory factor.
Also, does the firmware version make a difference?
Either of these might account for the different behaviour between different camera body/lens combinations.

Just a wild punt - but maybe it's an interaction between your shooting style and the cameras. Does the K5II achieve focus faster than the 5? If so it might be that you are getting the shot faster and the stabilisation doesn't have time to settle.