Back button focus and IS

[Mystery57]

Ive got my 650D set up for the back button focus as was discussed elsewhere on here.

When using my 70-200 IS USM lens, I obviously have Image Shake control built into it.

My question is (hope its not daft)

When I use back button focus with other lens, after focussing I remove my finger from the button and concentrate on the exposure using the camera main button then take the photo.

If I do this with the zoom lens will the IS still work, or does the shutter focus button have to remain pushed down as well ?


cheers
Andrew

 

[rpsmith79]

I don't see why not, the IS will be linked to the shutter release, not to the focus button

Why not give it a go with the IS turned on and off and see if you can see if it works or not

 

[tdodd]

IS works (assuming it's enabled) both when using the AF-On button and when half pressing the shutter button. I would be surprised if you could not feel/hear/see it turning on and off when pressing and releasing the buttons. It should turn on instantly when either button is pressed and will remain on for a couple of seconds after either button is released.

 

[buckas]

what tim says

 

[Mystery57]

Thanks Guys, only just had this particular lens (as an upgrade) and thought the noise was probably the IS kicking in - hence posting the "stupid" question.

cheers

 

[PistolPeteUK]

I was told to let the IS run for about a second to let the stabilisation... erm.. stabilise.
On my 70-200 f/2.8 IS II I can certainly hear a "spinning up" period followed by a more stable regular noise.

 

[Mystery57]

What confused me as Pete has described, was the spinning noise as I had not encountered that with previous lenses