[GaryT]

I have a new K1 and want to use Shake Reduction with my Pentax KA zoom lenses. If I set a middle value for my zoom's focal length (eg 50mm for my 35-70mm zoom, 135mm for my 70-210mm zoom, 70mm my 35-105mm zoom) when asked by the camera to input the lens' focal length the SR will work OK for that mid point but presumably less well for the widest and longest setting for my zoom lens.
Of course I can reset it and switch the camera off and on to tell the camera what is my actual zoom setting when I change my focal length but this makes using the zoom at different settings much slower and I'd rather not do that, as I could always use one of my prime lenses instead.
So I wondered whether anyone has practical experience of using SR in such situations?
Am I better off switching SR off when using manual zoom lenses to get sharper results if I wish to zoom in and out quickly for different shots, or will setting an average value for the focal length and leaving it at that setting even if I zoom in and out give sharper results?

[photolady95]

Check your manual. I don't have a K-1 but on any of my cameras, i.e., K-50; K-30; Kx, there is a menu setting to allow you to change focal length without having to turn the camera off and back on.

[Adam]

Of course I can reset it and switch the camera off and on to tell the camera what is my actual zoom setting when I change my focal length but this makes using the zoom at different settings much slower and I'd rather not do that, as I could always use one of my prime lenses instead.

Indeed, it can be changed via the main menu. There are a lot of schools of thought on this, but I agree that keeping the value at the lower end of the range is the way to go if you want to set it and forget it.

I have the focal length in the quick/info-button menu so it may quickly be editable.

[Topsy]

And if you have it set to the info button your can simply scroll through the lengths with one of the wheels.

[GaryT]

Thanks.. This is all v helpful. I have now managed to get the focal length able to be set without turning off the camera by using the control panel and changing one of the defaults to 'focal length'.
I think I see the logic of setting not a mid value but the lowest value, as the sensor would presumably move a lot more to adjust for shake when set to higher focal lengths than set to a wider angle(?)
I'm just glad to be able to use my many Full Frame Pentax legacy lenses and try to get the best out of them. I have a couple of digital crop lenses from when I had a K20D (a standard zoom and the 40mm pancake which seems to cover Full Frame). Perhaps in the future I'll get some FF digital autofocus lenses but I'll explore my legacy lenses first and get to grips with the many functions of the K1!